diff --git a/components/fpspreadsheet/examples/fpsgrid/fpsgrid.lpi b/components/fpspreadsheet/examples/fpsgrid/fpsgrid.lpi
index 1d5216e28..e8dbb9b11 100644
--- a/components/fpspreadsheet/examples/fpsgrid/fpsgrid.lpi
+++ b/components/fpspreadsheet/examples/fpsgrid/fpsgrid.lpi
@@ -129,7 +129,7 @@
         <EditorIndex Value="1"/>
         <WindowIndex Value="0"/>
         <TopLine Value="511"/>
-        <CursorPos X="27" Y="526"/>
+        <CursorPos X="21" Y="524"/>
         <UsageCount Value="200"/>
         <Loaded Value="True"/>
         <LoadedDesigner Value="True"/>
@@ -137,10 +137,11 @@
       <Unit2>
         <Filename Value="..\..\fpspreadsheet.pas"/>
         <UnitName Value="fpspreadsheet"/>
+        <IsVisibleTab Value="True"/>
         <EditorIndex Value="5"/>
         <WindowIndex Value="0"/>
         <TopLine Value="523"/>
-        <CursorPos X="40" Y="533"/>
+        <CursorPos X="22" Y="533"/>
         <UsageCount Value="100"/>
         <Bookmarks Count="1">
           <Item0 X="68" Y="3716" ID="1"/>
@@ -231,11 +232,10 @@
       <Unit13>
         <Filename Value="..\..\fpsutils.pas"/>
         <UnitName Value="fpsutils"/>
-        <IsVisibleTab Value="True"/>
         <EditorIndex Value="2"/>
         <WindowIndex Value="0"/>
         <TopLine Value="279"/>
-        <CursorPos X="52" Y="316"/>
+        <CursorPos X="38" Y="292"/>
         <UsageCount Value="69"/>
         <Loaded Value="True"/>
       </Unit13>
diff --git a/components/fpspreadsheet/fpspreadsheet.pas b/components/fpspreadsheet/fpspreadsheet.pas
index 0c98e5188..467707594 100755
--- a/components/fpspreadsheet/fpspreadsheet.pas
+++ b/components/fpspreadsheet/fpspreadsheet.pas
@@ -75,7 +75,7 @@ type
     fekCell, fekCellRef, fekCellRange, fekNum, fekInteger, fekString, fekBool,
     fekErr, fekMissingArg,
     { Basic operations }
-    fekAdd, fekSub, fekDiv, fekMul, fekPercent, fekPower, fekUMinus, fekUPlus,
+    fekAdd, fekSub, fekMul, fekDiv, fekPercent, fekPower, fekUMinus, fekUPlus,
     fekConcat,  // string concatenation
     fekEqual, fekGreater, fekGreaterEqual, fekLess, fekLessEqual, fekNotEqual,
     fekParen,
@@ -141,14 +141,15 @@ type
     cctUTF8String, cctDateTime, cctBool, cctError);
 
   {@@ Error code values }
-  TErrorValue = (
+  TsErrorValue = (
+    errOK,                 // no error
     errEmptyIntersection,  // #NULL!
     errDivideByZero,       // #DIV/0!
     errWrongType,          // #VALUE!
     errIllegalRef,         // #REF!
     errWrongName,          // #NAME?
     errOverflow,           // #NUM!
-    errArgNotAvail,        // #N/A
+    errArgError,           // #N/A
     // --- no Excel errors --
     errFormulaNotSupported
   );
@@ -314,7 +315,7 @@ type
     UTF8StringValue: ansistring;
     DateTimeValue: TDateTime;
     BoolValue: Boolean;
-    StatusValue: Byte;
+    ErrorValue: TsErrorValue;
     { Formatting fields }
     { When adding/deleting formatting fields don't forget to update CopyFormat! }
     UsedFormattingFields: TsUsedFormattingFields;
@@ -419,8 +420,8 @@ type
       AFormat: TsNumberFormat = nfShortDateTime; AFormatStr: String = ''); overload;
     procedure WriteDateTime(ACell: PCell; AValue: TDateTime;
       AFormat: TsNumberFormat = nfShortDateTime; AFormatStr: String = ''); overload;
-    procedure WriteErrorValue(ARow, ACol: Cardinal; AValue: TErrorValue); overload;
-    procedure WriteErrorValue(ACell: PCell; AValue: TErrorValue); overload;
+    procedure WriteErrorValue(ARow, ACol: Cardinal; AValue: TsErrorValue); overload;
+    procedure WriteErrorValue(ACell: PCell; AValue: TsErrorValue); overload;
     procedure WriteFormula(ARow, ACol: Cardinal; AFormula: TsFormula);
     procedure WriteNumber(ARow, ACol: Cardinal; ANumber: double;
       AFormat: TsNumberFormat = nfGeneral; ADecimals: Byte = 2;
@@ -797,7 +798,7 @@ resourcestring
   lpErrIllegalRef = '#REF!';
   lpErrWrongName = '#NAME?';
   lpErrOverflow = '#NUM!';
-  lpErrArgNotAvail = '#N/A';
+  lpErrArgError = '#N/A';
   lpErrFormulaNotSupported = '<FORMULA?>';
 
 var
@@ -879,8 +880,8 @@ const
   { Basic operations }
     (Symbol:'+';         MinParams:2; MaxParams:2),   // fekAdd
     (Symbol:'-';         MinParams:2; MaxParams:2),   // fekSub
-    (Symbol:'*';         MinParams:2; MaxParams:2),   // fekDiv
-    (Symbol:'/';         MinParams:2; MaxParams:2),   // fekMul
+    (Symbol:'*';         MinParams:2; MaxParams:2),   // fekMul
+    (Symbol:'/';         MinParams:2; MaxParams:2),   // fekDiv
     (Symbol:'%';         MinParams:1; MaxParams:1),   // fekPercent
     (Symbol:'^';         MinParams:2; MaxParams:2),   // fekPower
     (Symbol:'-';         MinParams:1; MaxParams:1),   // fekUMinus
@@ -1488,14 +1489,14 @@ begin
       cctBool:
         Result := IfThen(BoolValue, lpTRUE, lpFALSE);
       cctError:
-        case TErrorValue(StatusValue and $0F) of
+        case TsErrorValue(ErrorValue) of
           errEmptyIntersection  : Result := lpErrEmptyIntersection;
           errDivideByZero       : Result := lpErrDivideByZero;
           errWrongType          : Result := lpErrWrongType;
           errIllegalRef         : Result := lpErrIllegalRef;
           errWrongName          : Result := lpErrWrongName;
           errOverflow           : Result := lpErrOverflow;
-          errArgNotAvail        : Result := lpErrArgNotAvail;
+          errArgError           : Result := lpErrArgError;
           errFormulaNotSupported: Result := lpErrFormulaNotSupported;
         end;
       else
@@ -1548,6 +1549,7 @@ end;
 
 function TsWorksheet.ReadRPNFormulaAsString(ACell: PCell): String;
 var
+  fs: TFormatSettings;
   formula: TsRPNFormula;
   elem: TsFormulaElement;
   i, j: Integer;
@@ -1555,18 +1557,12 @@ var
   s: String;
   ptr: Pointer;
   fek: TFEKind;
-
-  procedure Store(s: String);
-  begin
-    L.Clear;
-    L.Add(s);
-  end;
-
 begin
   Result := '';
   if ACell = nil then
     exit;
 
+  fs := Workbook.FormatSettings;
   L := TStringList.Create;
   try
     for i:=0 to Length(ACell^.RPNFormulaValue)-1 do begin
@@ -1574,42 +1570,21 @@ begin
       ptr := Pointer(elem.ElementKind);
       case elem.ElementKind of
         fekNum:
-          L.AddObject(Format('%g', [elem.DoubleValue]), ptr);
+          L.AddObject(Format('%g', [elem.DoubleValue], fs), ptr);
         fekInteger:
           L.AddObject(IntToStr(elem.IntValue), ptr);
         fekString:
           L.AddObject('"' + elem.StringValue + '"', ptr);
         fekBool:
-          L.AddObject(IfThen(elem.DoubleValue=0, 'TRUE', 'FALSE'), ptr);
+          L.AddObject(IfThen(boolean(elem.IntValue), 'FALSE', 'TRUE'), ptr);
         fekCell,
         fekCellRef:
           L.AddObject(GetCellString(elem.Row, elem.Col, elem.RelFlags), ptr);
         fekCellRange:
           L.AddObject(GetCellRangeString(elem.Row, elem.Col, elem.Row2, elem.Col2, elem.RelFlags), ptr);
         // Operations:
-        fekAdd         : L.AddObject('+', ptr);
-        fekSub         : L.AddObject('-', ptr);
-        fekMul         : L.AddObject('*', ptr);
-        fekDiv         : L.AddObject('/', ptr);
-        fekPower       : L.AddObject('^', ptr);
-        fekConcat      : L.AddObject('&', ptr);
-        fekParen       : L.AddObject('', ptr);
-        fekEqual       : L.AddObject('=', ptr);
-        fekNotEqual    : L.AddObject('<>', ptr);
-        fekLess        : L.AddObject('<', ptr);
-        fekLessEqual   : L.AddObject('<=', ptr);
-        fekGreater     : L.AddObject('>', ptr);
-        fekGreaterEqual: L.AddObject('>=', ptr);
-        fekPercent     : L.AddObject('%', ptr);
-        fekUPlus       : L.AddObject('+', ptr);
-        fekUMinus      : L.AddObject('-', ptr);
-        fekCellInfo    : L.AddObject('CELL', ptr);         // That's the function name!
         else
-          begin
-            s := GetEnumName(TypeInfo(TFEKind), integer(elem.ElementKind));
-            Delete(s, 1, 3);
-            L.AddObject(s, ptr);
-          end;
+          L.AddObject(FEProps[elem.ElementKind].Symbol, ptr);
       end;
     end;
 
@@ -1619,39 +1594,56 @@ begin
       case fek of
         fekAdd, fekSub, fekMul, fekDiv, fekPower, fekConcat,
         fekEqual, fekNotEqual, fekLess, fekLessEqual, fekGreater, fekGreaterEqual:
-          begin
+          if i+2 < L.Count then begin
             L.Strings[i] := Format('%s%s%s', [L[i+2], L[i], L[i+1]]);
-            L.Objects[i] := pointer(fekString);
             L.Delete(i+2);
             L.Delete(i+1);
+            L.Objects[i] := pointer(fekString);
+          end else begin
+            Result := '=' + lpErrArgError;
+            exit;
           end;
         fekUPlus, fekUMinus:
-          begin
+          if i+1 < L.Count then begin
             L.Strings[i] := L[i]+L[i+1];
-            L.Objects[i] := Pointer(fekString);
             L.Delete(i+1);
+            L.Objects[i] := Pointer(fekString);
+          end else begin
+            Result := '=' + lpErrArgError;
+            exit;
           end;
         fekPercent:
-          begin
+          if i+1 < L.Count then begin
             L.Strings[i] := L[i+1]+L[i];
-            L.Objects[i] := Pointer(fekString);
             L.Delete(i+1);
+            L.Objects[i] := Pointer(fekString);
+          end else begin
+            Result := '=' + lpErrArgError;
+            exit;
           end;
         fekParen:
-          begin
+          if i+1 < L.Count then begin
             L.Strings[i] := Format('(%s)', [L[i+1]]);
-            L.Objects[i] := pointer(fekString);
             L.Delete(i+1);
+            L.Objects[i] := pointer(fekString);
+          end else begin
+            Result := '=' + lpErrArgError;
+            exit;
           end;
         else
           if fek >= fekAdd then begin
             elem := ACell^.RPNFormulaValue[i];
             s := '';
             for j:= i+elem.ParamsNum downto i+1 do begin
-              s := s + ',' + L[j];
-              L.Delete(j);
+              if j < L.Count then begin
+                s := s + fs.ListSeparator + ' ' + L[j];
+                L.Delete(j);
+              end else begin
+                Result := '=' + lpErrArgError;
+                exit;
+              end;
             end;
-            Delete(s, 1, 1);
+            Delete(s, 1, 2);
             L.Strings[i] := Format('%s(%s)', [L[i], s]);
             L.Objects[i] := pointer(fekString);
           end;
@@ -1659,7 +1651,10 @@ begin
       dec(i);
     end;
 
-    Result := '=' + L[0];
+    if L.Count > 1 then
+      Result := '=' + lpErrArgError  // too many arguments
+    else
+      Result := '=' + L[0];
 
   finally
     L.Free;
@@ -1920,16 +1915,16 @@ end;
   @param  ACol       The column of the cell
   @param  AValue     The error code value
 }
-procedure TsWorksheet.WriteErrorValue(ARow, ACol: Cardinal; AValue: TErrorValue);
+procedure TsWorksheet.WriteErrorValue(ARow, ACol: Cardinal; AValue: TsErrorValue);
 begin
   WriteErrorValue(GetCell(ARow, ACol), AValue);
 end;
 
-procedure TsWorksheet.WriteErrorValue(ACell: PCell; AValue: TErrorValue);
+procedure TsWorksheet.WriteErrorValue(ACell: PCell; AValue: TsErrorValue);
 begin
   if ACell <> nil then begin
     ACell^.ContentType := cctError;
-    ACell^.StatusValue := (ACell^.StatusValue and $F0) or ord(AValue);
+    ACell^.ErrorValue := AValue;
     ChangedCell(ACell^.Row, ACell^.Col);
   end;
 end;
@@ -3927,7 +3922,6 @@ begin
     raise Exception.CreateFmt(lpSpecifyNumberOfParams, [FEProps[AToken].Symbol]);
 
   Result := RPNFunc(AToken, FEProps[AToken].MinParams, ANext);
-  Result^.Next := ANext;
 end;
 
 {@@
diff --git a/components/fpspreadsheet/fpsutils.pas b/components/fpspreadsheet/fpsutils.pas
index 8c31c29f9..7cee8c2a6 100644
--- a/components/fpspreadsheet/fpsutils.pas
+++ b/components/fpspreadsheet/fpsutils.pas
@@ -62,6 +62,8 @@ function GetColString(AColIndex: Integer): String;
 function GetCellString(ARow,ACol: Cardinal; AFlags: TsRelFlags): String;
 function GetCellRangeString(ARow1, ACol1, ARow2, ACol2: Cardinal; AFlags: TsRelFlags): String;
 
+function GetErrorValueStr(AErrorValue: TsErrorValue): String;
+
 function UTF8TextToXMLText(AText: ansistring): ansistring;
 
 function TwipsToMillimeters(AValue: Integer): Single;
@@ -431,19 +433,20 @@ begin
   Result := Char(AValue + ord('A'));
 end;
 
+{ Calculates an Excel column name ('A', 'B' etc) from the zero-based column index }
 function GetColString(AColIndex: Integer): String;
+{ Code adapted from: http://stackoverflow.com/questions/12796973/vba-function-to-convert-column-number-to-letter }
+var
+  n: Integer;
+  c: byte;
 begin
-  if AColIndex < 26 then
-    Result := Letter(AColIndex)
-  else
-  if AColIndex < 26*26 then
-    Result := Letter(AColIndex div 26) + Letter(AColIndex mod 26)
-  else
-  if AColIndex < 26*26*26 then
-    Result := Letter(AColIndex div (26*26)) + Letter((AColIndex mod (26*26)) div 26)
-      + Letter(AColIndex mod (26*26*26))
-  else
-    Result := 'too big';
+  Result := '';
+  n := AColIndex + 1;
+  while (n > 0) do begin
+    c := (n - 1) mod 26;
+    Result := char(c + ord('A')) + Result;
+    n := (n - c) div 26;
+  end;
 end;
 
 const
@@ -469,6 +472,24 @@ begin
 end;
 
 
+{ Returns the message text assigned to an error value }
+function GetErrorValueStr(AErrorValue: TsErrorValue): String;
+begin
+  case AErrorValue of
+    errOK                   : Result := '';
+    errEmptyIntersection    : Result := '#NULL!';
+    errDivideByZero         : Result := '#DIV/0!';
+    errWrongType            : Result := '#VALUE!';
+    errIllegalRef           : Result := '#REF!';
+    errWrongName            : Result := '#NAME?';
+    errOverflow             : Result := '#NUM!';
+    errArgError             : Result := '#N/A';
+    // --- no Excel errors --
+    errFormulaNotSupported  : Result := '#FORMULA?';
+    else                      Result := '#UNKNOWN ERROR';
+  end;
+end;
+
 {In XML files some chars must be translated}
 function UTF8TextToXMLText(AText: ansistring): ansistring;
 var
diff --git a/components/fpspreadsheet/tests/formulatests.pas b/components/fpspreadsheet/tests/formulatests.pas
index 9e17dc706..c11d70a73 100644
--- a/components/fpspreadsheet/tests/formulatests.pas
+++ b/components/fpspreadsheet/tests/formulatests.pas
@@ -26,6 +26,10 @@ type
   published
     // Writes out numbers & reads back.
     // If previous read tests are ok, this effectively tests writing.
+    { BIFF2 Tests }
+    procedure TestWriteReadBIFF2_FormulaStrings;
+    { BIFF5 Tests }
+    procedure TestWriteReadBIFF5_FormulaStrings;
     { BIFF8 Tests }
     procedure TestWriteReadBIFF8_FormulaStrings;
   end;
@@ -33,7 +37,7 @@ type
 implementation
 
 uses
-  rpnFormulaUnit;
+  fpsUtils, rpnFormulaUnit;
 
 { TSpreadWriteReadFormatTests }
 
@@ -59,21 +63,28 @@ var
   expected: String;
   actual: String;
   cell: PCell;
+  fs: TFormatSettings;
 begin
   TempFile := GetTempFileName;
 
   // Create test workbook
   MyWorkbook := TsWorkbook.Create;
+//  MyWorkbook.FormatSettings.DecimalSeparator := '.';
+//  MyWorkbook.FormatSettings.ShortDateFormat := 'yyyy-mm-dd';
   MyWorkSheet:= MyWorkBook.AddWorksheet(SHEET);
 
   // Write out all test formulas
   // All formulas are in column B
-  WriteRPNFormulaSamples(MyWorksheet, AFormat);
+  WriteRPNFormulaSamples(MyWorksheet, AFormat, true);
   MyWorkBook.WriteToFile(TempFile, AFormat, true);
   MyWorkbook.Free;
 
   // Open the spreadsheet
   MyWorkbook := TsWorkbook.Create;
+  MyWorkbook.ReadFormulas := true;
+//  MyWorkbook.FormatSettings.DecimalSeparator := '.';
+//  MyWorkbook.FormatSettings.ShortDateFormat := 'yyyy-mm-dd';
+
   MyWorkbook.ReadFromFile(TempFile, AFormat);
   if AFormat = sfExcel2 then
     MyWorksheet := MyWorkbook.GetFirstWorksheet
@@ -86,7 +97,7 @@ begin
     if (cell <> nil) and (Length(cell^.RPNFormulaValue) > 0) then begin
       actual := MyWorksheet.ReadRPNFormulaAsString(cell);
       expected := MyWorksheet.ReadAsUTF8Text(Row, 0);
-      CheckEquals(actual, expected, 'Test read formula mismatch, cell '+CellNotation(MyWorkSheet,Row,Col));
+      CheckEquals(expected, actual, 'Test read formula mismatch, cell '+CellNotation(MyWorkSheet,Row,1));
     end;
   end;
 
@@ -95,12 +106,21 @@ begin
   DeleteFile(TempFile);
 end;
 
+procedure TSpreadWriteReadFormulaTests.TestWriteReadBIFF2_FormulaStrings;
+begin
+  TestWriteReadFormulaStrings(sfExcel2);
+end;
+
+procedure TSpreadWriteReadFormulaTests.TestWriteReadBIFF5_FormulaStrings;
+begin
+  TestWriteReadFormulaStrings(sfExcel5);
+end;
+
 procedure TSpreadWriteReadFormulaTests.TestWriteReadBIFF8_FormulaStrings;
 begin
   TestWriteReadFormulaStrings(sfExcel8);
 end;
 
-
 initialization
   // Register so these tests are included in a full run
   RegisterTest(TSpreadWriteReadFormulaTests);
diff --git a/components/fpspreadsheet/tests/manualtests.pas b/components/fpspreadsheet/tests/manualtests.pas
index 4c749e749..3f696e441 100644
--- a/components/fpspreadsheet/tests/manualtests.pas
+++ b/components/fpspreadsheet/tests/manualtests.pas
@@ -212,7 +212,7 @@ begin
     Workbook := TsWorkbook.Create;
 
   Worksheet := Workbook.AddWorksheet(RPNSHEETNAME);
-  WriteRPNFormulaSamples(Worksheet, OUTPUT_FORMAT);
+  WriteRPNFormulaSamples(Worksheet, OUTPUT_FORMAT, false);
 end;
 {$ENDIF}
 
diff --git a/components/fpspreadsheet/tests/rpnformulaunit.pas b/components/fpspreadsheet/tests/rpnformulaunit.pas
index ea525dd8d..1d4721a8a 100644
--- a/components/fpspreadsheet/tests/rpnformulaunit.pas
+++ b/components/fpspreadsheet/tests/rpnformulaunit.pas
@@ -5,7 +5,8 @@ interface
 uses
   SysUtils, fpspreadsheet,fpsutils;
 
-procedure WriteRPNFormulaSamples(Worksheet: TsWorksheet; AFormat: TsSpreadsheetFormat);
+procedure WriteRPNFormulaSamples(Worksheet: TsWorksheet;
+  AFormat: TsSpreadsheetFormat; IncludeErrors: Boolean);
 
 implementation
 
@@ -15,7 +16,8 @@ uses
 const
   FALSE_TRUE: array[Boolean] of String = ('FALSE', 'TRUE');
 
-procedure WriteRPNFormulaSamples(Worksheet: TsWorksheet; AFormat: TsSpreadSheetFormat);
+procedure WriteRPNFormulaSamples(Worksheet: TsWorksheet;
+  AFormat: TsSpreadSheetFormat; IncludeErrors: Boolean);
 const
   cellB1 = 1.0;
   cellC1 = 2.0;
@@ -31,12 +33,23 @@ var
   value: Double;
   r,c: integer;
   celladdr: String;
+  fs: TFormatSettings;
+  ls: char;
 begin
   if Worksheet = nil then
     exit;
 
+  fs := Worksheet.Workbook.FormatSettings;
+  ls := fs.ListSeparator;
+  { When fpspreadsheet creates a formula string it uses the list separator of
+    the formatting to separate arguments. Therefore, we insert the list separator
+    in the expected formula strings as well. Unfortunately, these strings look
+    a bit inconvenient here:
+    '=SUM(A1, B1)'  becomes  Format('=SUM(A1%s B1)', [ls])  }
+
   Worksheet.WriteUTF8Text(0, 0, SBaseCells);
   Worksheet.WriteUsedFormatting(0, 0, [uffBold]);
+
   Worksheet.WriteNumber(0,1, cellB1);
   Worksheet.WriteNumber(0,2, cellC1);
   Worksheet.WriteNumber(0,3, cellD1);
@@ -58,8 +71,8 @@ begin
 
   // Numbers
   inc(Row);
-  value := 1.2345;
-  Worksheet.WriteUTF8Text(Row, 0, '=1.2345');
+  value := 1.2;
+  Worksheet.WriteUTF8Text(Row, 0, '='+Format('%.1f', [value], fs));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(value,
     nil))
@@ -271,7 +284,7 @@ begin
 
   // String concatenation
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '="Hello " & "world"');
+  Worksheet.WriteUTF8Text(Row, 0, '="Hello "&"world"');
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString('Hello ',
     RPNString('world',
@@ -495,9 +508,9 @@ begin
     nil))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[not (cellC1=cellC1)]);
 
-  // Logical AND - case false/false
+  // Logical AND - case false/false       =AND(1=0, 1=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=AND(1=0,1=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=AND(1=0%s 1=2)',[ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(0,
@@ -509,9 +522,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=0) and (1=2)]);
 
-  // Logical AND - case false/true
+  // Logical AND - case false/true       =AND(1=0, 2=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=AND(1=0,2=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=AND(1=0%s 2=2)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(0,
@@ -523,9 +536,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=0) and (2=2)]);
 
-  // Logical AND - case true/true
+  // Logical AND - case true/true         =AND(1=1, 2=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=AND(1=1,2=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=AND(1=1%s 2=2)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(1,
@@ -537,9 +550,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=1) and (2=2)]);
 
-  // Logical OR - case false/false
+  // Logical OR - case false/false       =OR(1=0, 1=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=OR(1=0,1=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=OR(1=0%s 1=2)',[ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(0,
@@ -551,9 +564,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=0) or (1=2)]);
 
-  // Logical OR - case false/true
+  // Logical OR - case false/true         =OR(1=0, 2=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=OR(1=0,2=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=OR(1=0%s 2=2)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(0,
@@ -565,9 +578,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=0) or (2=2)]);
 
-  // Logical OR - case true/true
+  // Logical OR - case true/true        =OR(1=1, 2=2)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=OR(1=1,2=2)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=OR(1=1%s 2=2)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(1,
     RPNNumber(1,
@@ -579,9 +592,9 @@ begin
     nil)))))))));
   Worksheet.WriteUTF8Text(Row, 2, FALSE_TRUE[(1=1) or (2=2)]);
 
-  // IF - case true
+  // IF - case true                       =IF(B1=1, "correct", "wrong")
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=IF(B1=1,"correct","wrong")');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=IF(B1=1%s "correct"%s "wrong")', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('B1',
     RPNNumber(1,
@@ -592,9 +605,9 @@ begin
     nil))))))));
   Worksheet.WriteUTF8Text(Row, 2, IfThen(cellB1=1.0, 'correct', 'wrong'));
 
-  // IF - case false
+  // IF - case false                      =IF(B1<>1, "correct", "wrong")
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=IF(B1<>1,"correct","wrong")');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=IF(B1<>1%s "correct"%s "wrong")', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('B1',
     RPNNumber(1,
@@ -605,9 +618,9 @@ begin
     nil))))))));
   Worksheet.WriteUTF8Text(Row, 2, IfThen(cellB1<>1.0, 'correct', 'wrong'));
 
-  // IF - case true (2 params)
+  // IF - case true (2 params)            =IF(B1=1, "correct")
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=IF(B1=1,"correct")');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=IF(B1=1%s "correct")', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('B1',
     RPNNumber(1,
@@ -617,9 +630,9 @@ begin
     nil)))))));
   Worksheet.WriteUTF8Text(Row, 2, IfThen(cellB1=1.0, 'correct', 'FALSE'));
 
-  // IF - case false (2 params)
+  // IF - case false (2 params)    =IF(B1<>1, "correct")
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=IF(B1<>1,"correct")');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=IF(B1<>1%s "correct")', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('B1',
     RPNNumber(1,
@@ -732,10 +745,10 @@ begin
     nil))))));
   Worksheet.WriteNumber(Row, 2, sin(pi/2));
 
-  // arcsin(0.5)
+  // arcsin(0.5)                         =ASIN(0.5)
   inc(Row);
   value := 0.5;
-  Worksheet.WriteUTF8Text(Row, 0, '=ASIN(0.5)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=ASIN(%.1f)', [value], fs));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(value,
     RPNFunc(fekASIN,
@@ -751,10 +764,10 @@ begin
     nil))));
   Worksheet.WriteNumber(Row, 2, cos(pi));
 
-  // arccos(0.5)
+  // arccos(0.5)                          =ACOS(0.5)
   inc(Row);
   value := 0.5;
-  Worksheet.WriteUTF8Text(Row, 0, '=ACOS(0.5)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=ACOS(%.1f)', [value], fs));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(value,
     RPNFunc(fekACOS,
@@ -795,10 +808,10 @@ begin
       nil))));
     Worksheet.WriteNumber(Row, 2, sinh(value));
 
-    // arcsinh
+    // arcsinh                              =ASIN(0.5)
     inc(Row);
     value := 0.5;
-    Worksheet.WriteUTF8Text(Row, 0, '=ASINH(0.5)');
+    Worksheet.WriteUTF8Text(Row, 0, Format('=ASINH(%.1f)', [value], fs));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(value,
       RPNFunc(fekASINH,
@@ -817,8 +830,8 @@ begin
 
     // arccosh
     inc(Row);
-    value := 10.0;
-    Worksheet.WriteUTF8Text(Row, 0, '=ACOSH(10.0)');
+    value := 10;
+    Worksheet.WriteUTF8Text(Row, 0, '=ACOSH(10)');
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(value,
       RPNFunc(fekACOSH,
@@ -835,10 +848,10 @@ begin
       nil))));
     Worksheet.WriteNumber(Row, 2, tanh(value));
 
-    // arctanh
+    // arctanh                              =ATANH(0.5)
     inc(Row);
     value := 0.5;
-    Worksheet.WriteUTF8Text(Row, 0, '=ATANH(0.5)');
+    Worksheet.WriteUTF8Text(Row, 0, Format('=ATANH(%.1f)', [value], fs));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(value,
       RPNFunc(fekATANH,
@@ -876,20 +889,16 @@ begin
     nil))));
   Worksheet.WriteNumber(Row, 2, ln(value));
 
-  // log to any basis
-  if AFormat <> sfExcel2 then begin
-    // This test is not working in Excel 2.
-    // Not clear if this is correct, need to debug later
-    inc(Row);
-    value := 256;
-    Worksheet.WriteUTF8Text(Row, 0, '=LOG(256,2)');
-    Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-      RPNNumber(value,
-      RPNNumber(2,
-      RPNFunc(fekLOG, 2,
-      nil)))));
-    Worksheet.WriteNumber(Row, 2, logn(2.0, value));
-  end;
+  // log to any basis                 =LOG(256, 2)
+  inc(Row);
+  value := 256;
+  Worksheet.WriteUTF8Text(Row, 0, Format('=LOG(256%s 2)', [ls]));
+  Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+    RPNNumber(value,
+    RPNNumber(2,
+    RPNFunc(fekLOG, 2,
+    nil)))));
+  Worksheet.WriteNumber(Row, 2, logn(2.0, value));
 
   // log10(100)
   inc(Row);
@@ -904,7 +913,7 @@ begin
   // log10(0.01)
   inc(Row);
   value := 0.01;
-  Worksheet.WriteUTF8Text(Row, 0, '=LOG10(0.01)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=LOG10(%.2f)', [value], fs));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(value,
     RPNFunc(fekLOG10,
@@ -918,9 +927,9 @@ begin
   Worksheet.WriteUTF8Text(Row, 0, 'Rounding');
   Worksheet.WriteUsedFormatting(Row, 0, [uffBold]);
 
-  // Round positive number to 1 decimal
+  // Round positive number to 1 decimal     =ROUND($F$1, 1)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=ROUND($F$1,1)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=ROUND($F$1%s 1)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$F$1',
     RPNNumber(1,
@@ -928,9 +937,9 @@ begin
     nil)))));
   Worksheet.WriteNumber(Row, 2, Round(cellF1*10)/10); //RoundTo(cellF1, 1));
 
-  // Round negative number to 1 decimal
+  // Round negative number to 1 decimal        =ROUND(G1, 1)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=ROUND(G1,1)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=ROUND(G1%s 1)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('G1',
     RPNNumber(1,
@@ -1036,7 +1045,7 @@ begin
   inc(Row);
   Worksheet.WriteUTF8Text(Row, 0, '=ISERR(G1)');
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNCellValue('G2',
+    RPNCellValue('G1',
     RPNFunc(fekIsERR,
     nil))));
   Worksheet.WriteUTF8Text(Row, 2, 'FALSE');
@@ -1160,41 +1169,41 @@ begin
     nil))));
   Worksheet.WriteUTF8Text(Row, 2, 'TRUE');
 
-  // Cell information
+  // Cell information                     =CELL("Address", B80)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=CELL("Address",B80)');
+  Worksheet.WriteUTF8Text(Row, 0, Format('=CELL("Address"%s B80)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNString('address',
+    RPNString('Address',
     RPNCellRef('B80',            // note: CellRef instead of CellValue!
     RPNFunc(fekCELLINFO, 2,
     nil)))));
 
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=CELL("Filename",B80)');
+  inc(Row);                           //  =CELL("Filename", B80)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=CELL("Filename"%s B80)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNString('filename',
+    RPNString('Filename',
     RPNCellRef('B80',            // note: CellRef instead of CellValue!
     RPNFunc(fekCELLINFO, 2,
     nil)))));
 
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=CELL("Row",B80)');
+  inc(Row);                           //  =CELL("Row", B80)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=CELL("Row"%s B80)',[ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNString('row',
+    RPNString('Row',
     RPNCellRef('B80',            // note: CellRef instead of CellValue!
     RPNFunc(fekCELLINFO, 2,
     nil)))));
 
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=CELL("format",B80)');
+  inc(Row);                            // =CELL("format", B80)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=CELL("format"%s B80)', [ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString('format',
     RPNCellRef('B80',            // note: CellRef instead of CellValue!
     RPNFunc(fekCELLINFO, 2,
     nil)))));
 
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=CELL("color",B80)');
+  inc(Row);                            // =CELL("color", B80)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=CELL("color"%s B80)',[ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString('color',
     RPNCellRef('B80',            // note: CellRef instead of CellValue!
@@ -1267,8 +1276,8 @@ begin
   end;
 
   // Date  (build date from parts)
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=DATE(2014,1,25)');
+  inc(Row);                            // =DATE(2014, 1, 25)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=DATE(2014%s 1%s 25)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2014,
     RPNNumber(1,
@@ -1279,7 +1288,7 @@ begin
 
   // DateValue (string to date number)
   inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=DATEVALUE("25.01.2014")');
+  Worksheet.WriteUTF8Text(Row, 0, '=DATEVALUE("2014-01-25")');
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString('2014-01-25',
     RPNFunc(fekDATEVALUE,
@@ -1287,9 +1296,9 @@ begin
   Worksheet.WriteNumber(Row, 2, EncodeDate(2014,1,25));
 
   // DateDifference
-  if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=DATEDIF("2010-01-01",DATE(2014;1;25),"M")');
+  if AFormat >= sfExcel5 then begin
+    inc(Row);                             //=DATEDIF("2010-01-01", DATE(2014, 1, 25), "M")
+    Worksheet.WriteUTF8Text(Row, 0, Format('=DATEDIF("2010-01-01"%s DATE(2014%s 1%s 25)%s "M")', [ls, ls, ls, ls]));
     // Note: Dates must be ordered: Date1 < Date2 !!!
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNString('2010-01-01',
@@ -1304,8 +1313,8 @@ begin
   end;
 
   // Year
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=YEAR(DATE(2014,1,25))');
+  inc(Row);                            // =YEAR(DATE(2014, 1, 25))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=YEAR(DATE(2014%s 1%s 25))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2014,
     RPNNumber(1,
@@ -1316,8 +1325,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 2014);
 
   // Month
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=MONTH(DATE(2014,1,25))');
+  inc(Row);                            // =MONTH(DATE(2014, 1, 25))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=MONTH(DATE(2014%s 1%s 25))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2014,
     RPNNumber(1,
@@ -1328,8 +1337,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 1);
 
   // Day
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=DAY(DATE(2014,1,25))');
+  inc(Row);                            // =DAY(DATE(2014, 1, 25))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=DAY(DATE(2014%s 1%s 25))', [ls,ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2014,
     RPNNumber(1,
@@ -1340,8 +1349,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 25);
 
   // Weekday     - 2 params can be used, but not in BIFF2
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=WEEKDAY(DATE(2014,1,25))');
+  inc(Row);                            // =WEEKDAY(DATE(2014,1,25))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=WEEKDAY(DATE(2014%s 1%s 25))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2014,
     RPNNumber(1,
@@ -1360,8 +1369,8 @@ begin
   Worksheet.WriteNumber(Row, 2, DayOfWeek(EncodeDate(2014,1,25)));
 
   // Time  (build time from parts)
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=TIME(21, 10, 5)');
+  inc(Row);                            // =TIME(21,10,5)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=TIME(21%s 10%s 5)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(21,
     RPNNumber(10,
@@ -1380,8 +1389,8 @@ begin
   Worksheet.WriteNumber(Row, 2, EncodeTime(21, 10, 5, 0));
 
   // Hour
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=HOUR(TIME(21, 10, 5)))');
+  inc(Row);                            // =HOUR(TIME(21, 10, 5))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=HOUR(TIME(21%s 10%s 5))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(21,
     RPNNumber(10,
@@ -1392,8 +1401,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 21);
 
   // Minute
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=MINUTE(TIME(21, 10, 5)))');
+  inc(Row);                            // =MINUTE(TIME(21, 10, 5))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=MINUTE(TIME(21%s 10%s 5))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(21,
     RPNNumber(10,
@@ -1404,8 +1413,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 10);
 
   // Second
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=SECOND(TIME(21, 10, 5)))');
+  inc(Row);                            // =SECOND(TIME(21, 10, 5))
+  Worksheet.WriteUTF8Text(Row, 0, Format('=SECOND(TIME(21%s 10%s 5))', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(21,
     RPNNumber(10,
@@ -1423,8 +1432,8 @@ begin
   Worksheet.WriteUsedFormatting(Row, 0, [uffBold]);
 
   // Count - non-empty cells
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=COUNT($B$1,$C$1,$D$1:F1)');
+  inc(Row);                            // =COUNT($B$1, $C$1, $D$1:F1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=COUNT($B$1%s $C$1%s $D$1:F1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1434,8 +1443,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 5);  // 5 cells in total, all not empty
 
   // Count - with empty cells & alpha-numeric cells
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=COUNT($B$1,$C$1,$D$1:$F$2,"ABC")');
+  inc(Row);                            // =COUNT($B$1, $C$1, $D$1:$F$2, "ABC")
+  Worksheet.WriteUTF8Text(Row, 0, Format('=COUNT($B$1%s $C$1%s $D$1:$F$2%s "ABC")', [ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1446,8 +1455,8 @@ begin
   Worksheet.WriteNumber(Row, 2, 5);  // 5 non-empty, 3 empty
 
   // CountA - empty cells and constants
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=COUNTA($B$1,$C$1,$D$1:$F$2,"ABC","DEF")');
+  inc(Row);                             //=COUNTA($B$1, $C$1, D$1:$F$2, "ABC", "DEF")
+  Worksheet.WriteUTF8Text(Row, 0, Format('=COUNTA($B$1%s $C$1%s $D$1:$F$2%s "ABC"%s "DEF")', [ls, ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1460,8 +1469,8 @@ begin
 
   if AFormat <> sfExcel2 then begin
     // CountIF
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=COUNTIF(A1:G1,"<=1")');
+    inc(Row);                           // =COUNTIF(A1:G1, "<=1")
+    Worksheet.WriteUTF8Text(Row, 0, Format('=COUNTIF(A1:G1%s "<=1")', [ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNCellRange('A1:G1',
       RPNString('<=1',
@@ -1484,20 +1493,20 @@ begin
   end;
 
   // Sum - non-empty cells
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=SUM($B$1,$C$1,D$1:F$1)');
+  inc(Row);                            // =SUM($B$1, $C$1, D$1:F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=SUM($B$1%s $C$1%s D$1:F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
-    RPNCellRange('$D$1:F$1',
+    RPNCellRange('D$1:F$1',
     RPNFunc(fekSUM, 3,
     nil))))));
   Worksheet.WriteNumber(Row, 2, cellB1+cellC1+cellD1+cellE1+cellF1);
 
   if AFormat <> sfExcel2 then begin
     // SumIF
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=SUMIF(A1:G1,"<=1")');
+    inc(Row);                            // =SUMIF(A1:G1, "<=1")
+    Worksheet.WriteUTF8Text(Row, 0, Format('=SUMIF(A1:G1%s "<=1")', [ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNCellRange('A1:G1',
       RPNString('<=1',
@@ -1510,8 +1519,8 @@ begin
     );
 
     // Sum of squares
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=SUMSQ($B$1,$C$1,$D$1:$F$1)');
+    inc(Row);                            // =SUMSQ($B$1, $C$1, $D$1:$F$1)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=SUMSQ($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNCellValue('$B$1',
       RPNCellValue('$C$1',
@@ -1522,8 +1531,8 @@ begin
   end;
 
   // Product
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=PRODUCT($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =PRODUCT($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=PRODUCT($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1533,8 +1542,8 @@ begin
   Worksheet.WriteNumber(Row, 2, cellB1*cellC1*cellD1*cellE1*cellF1);
 
   // Average - non-empty cells
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=AVERAGE($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =AVERAGE($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=AVERAGE($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1544,8 +1553,8 @@ begin
   Worksheet.WriteNumber(Row, 2, (cellB1+cellC1+cellD1+cellE1+cellF1)/5);
 
   // StdDev
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=STDEV($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =STDEV($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=STDEV($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1555,8 +1564,8 @@ begin
   Worksheet.WriteNumber(Row, 2, stddev([cellB1,cellC1,cellD1,cellE1,cellF1]));
 
   // Population StdDev
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=STDEVP($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =STDEVP($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=STDEVP($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1567,8 +1576,8 @@ begin
 
   // Average deviation
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=AVEDEV($B$1,$C$1,$D$1:$F$1)');
+    inc(Row);                            // =AVEDEV($B$1, $C$1, $D$1:$F$1)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=AVEDEV($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNCellValue('$B$1',
       RPNCellValue('$C$1',
@@ -1581,8 +1590,8 @@ begin
   end;
 
   // Variance
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=VAR($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =VAR($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=VAR($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1592,8 +1601,8 @@ begin
   Worksheet.WriteNumber(Row, 2, variance([cellB1,cellC1,cellD1,cellE1,cellF1]));
 
   // Population variance
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=VARP($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =VARP($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=VARP($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1603,8 +1612,8 @@ begin
   Worksheet.WriteNumber(Row, 2, popnvariance([cellB1,cellC1,cellD1,cellE1,cellF1]));
 
   // Max
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=MAX($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =MAX($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=MAX($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1614,8 +1623,8 @@ begin
   Worksheet.WriteNumber(Row, 2, MaxValue([cellB1,cellC1,cellD1,cellE1,cellF1]));
 
   // Min
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=MIN($B$1,$C$1,$D$1:$F$1)');
+  inc(Row);                            // =MIN($B$1, $C$1, $D$1:$F$1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=MIN($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNCellValue('$B$1',
     RPNCellValue('$C$1',
@@ -1626,8 +1635,8 @@ begin
 
   // Median
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=MEDIAN($B$1,$C$1,$D$1:$F$1)');
+    inc(Row);                            // =MEDIAN($B$1, $C$1, $D$1:$F$1)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=MEDIAN($B$1%s $C$1%s $D$1:$F$1)', [ls, ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNCellValue('$B$1',
       RPNCellValue('$C$1',
@@ -1639,11 +1648,12 @@ begin
 
   // Beta distribution
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=BETADIST(3,7.5,9,1,4)');
+    inc(Row);                            // =BETADIST(3, 7, 9, 1, 4)
+    value := 7.5;
+    Worksheet.WriteUTF8Text(Row, 0, Format('=BETADIST(3%s %.1f%s 9%s 1%s 4)', [ls, value, ls, ls, ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(3,
-      RPNNumber(7.5,
+      RPNNumber(value,
       RPNNumber(9,
       RPNNumber(1,
       RPNNumber(4,
@@ -1655,36 +1665,40 @@ begin
   // Inverse beta function
   if AFormat <> sfExcel2 then begin
     inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=BETAINV(0.3,7.5,9,1,4)');
+    value := 0.5;                        // =BETAINV(0.5, 7, 9, 1, 4)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=BETAINV(%.1f%s 7%s 9%s 1%s 4)', [value, ls, ls, ls, ls], fs));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-      RPNNumber(0.3,
-      RPNNumber(7.5,
+      RPNNumber(value,
+      RPNNumber(7,
       RPNNumber(9,
       RPNNumber(1,
       RPNNumber(4,
       RPNFunc(fekBETAINV, 5,
       nil))))))));
-    Worksheet.WriteNumber(Row, 2, 2.164759636);  // result according to http://www.techonthenet.com/excel/formulas/betainv.php
+    Worksheet.WriteNumber(Row, 2, 2.304498434);  // Result calculated by Excel
   end;
 
+
   // Binomial distribution
   if AFormat <> sfExcel2 then begin
     inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=BINOMDIST(3,8,0.35,TRUE)');
+    value := 0.5;                        // =BINOMDIST(3, 8, 0.5, TRUE)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=BINOMDIST(3%s 8%s %.1f%s TRUE)', [ls, ls, value, ls], fs));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(3,
       RPNNumber(8,
-      RPNNumber(0.35,
+      RPNNumber(0.5,
       RPNBool(true,
       RPNFunc(fekBINOMDIST,
       nil)))))));
-    Worksheet.WriteNumber(Row, 2, 0.706399436);  // result according to http://www.techonthenet.com/excel/formulas/binomdist.php
+    Worksheet.WriteNumber(Row, 2, 0.36328125);  // Result calculated by Excel
   end;
 
+
   // Chi2 distribution
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=CHIDIST(3,9)');
+    inc(Row);                            // =CHIDIST(3,9)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=CHIDIST(3%s 9)', [ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(3,
       RPNNumber(9,
@@ -1696,19 +1710,20 @@ begin
   // Inverse of Chi2 distribution
   if AFormat <> sfExcel2 then begin
     inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=CHIINV(0.3,7)');
+    value := 0.5;                       // '=CHIINV(0.5, 7)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=CHIINV(%.1f%s 7)', [value, ls], fs));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-      RPNNumber(0.3,
+      RPNNumber(0.5,
       RPNNumber(7,
       RPNFunc(fekCHIINV,
       nil)))));
-    Worksheet.WriteNumber(Row, 2,  8.38343064);  // result according to http://www.techonthenet.com/excel/formulas/chiinv.php
+    Worksheet.WriteNumber(Row, 2,  6.345811373);  // Result calculated by Excel
   end;
 
   // Permutations
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=PERMUT(21,5)');
+    inc(Row);                            // =PERMUT(21, 5)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=PERMUT(21%s 5)',[ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(21,
       RPNNumber(5,
@@ -1719,8 +1734,8 @@ begin
 
   // Poisson distribution
   if AFormat <> sfExcel2 then begin
-    inc(Row);
-    Worksheet.WriteUTF8Text(Row, 0, '=POISSON(1400,1500,TRUE)');
+    inc(Row);                            // =POISSON(1400, 1500, TRUE)
+    Worksheet.WriteUTF8Text(Row, 0, Format('=POISSON(1400%s 1500%s TRUE)', [ls, ls]));
     Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
       RPNNumber(1400,
       RPNNumber(1500,
@@ -1741,10 +1756,10 @@ begin
   // that earns 3.5% annually. You are going to deposit $250 at the beginning of
   // the month, each month, for 2 years.
   // according to: www.techonthenet.com/excel/formulas/fv.php
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=FV(3.5%/12,2*12,-250,-5000,1)');
+  inc(Row);                            // =FV(3%/12, 2*12, -250, -5000, 1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=FV(3%%/12%s 2*12%s -250%s -5000%s 1)', [ls, ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(3.5,
+    RPNNumber(3,
     RPNFunc(fekPERCENT,
     RPNNumber(12,
     RPNFunc(fekDIV,
@@ -1759,13 +1774,13 @@ begin
   Worksheet.WriteUTF8Text(Row, 2, '(not available in FPC)');
 
   // Present value of an investment that pays $250 at the end of every month for
-  // 2 years. The money paid out will earn 3.5% annually.
+  // 2 years. The money paid out will earn 3% annually.
   // according to: www.techonthenet.com/excel/formulas/pv.php
   // Note the missing argument!
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=PV(3.5%/12,2*12,250,,0)');
+  inc(Row);                            // =PV(3%/12, 2*12, 250, , 0)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=PV(3%%/12%s 2*12%s 250%s %s 0)', [ls, ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(3.5,
+    RPNNumber(3,
     RPNFunc(fekPercent,
     RPNNumber(12,
     RPNFunc(fekDIV,
@@ -1782,8 +1797,8 @@ begin
   // Interest rate on a $5,000 loan where monthly payments of $250 are made for
   // 2 years. All payments are made at the end of the period.
   // Adapted from //www.techonthenet.com/excel/formulas/rate.php
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=RATE(2*12,-250,5000)');
+  inc(Row);                            // =RATE(2*12, -250, 5000)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=RATE(2*12%s -250%s 5000)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNNumber(2,
     RPNNumber(12,
@@ -1801,10 +1816,10 @@ begin
   // Number of monthly payments of $150 for a $5,000 investment that earns
   // 3.5% annually. Payments are due at the end of the period.
   // Adapted from //www.techonthenet.com/excel/formulas/nper.php
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=NPER(3.5%/12,-150,5000)');
+  inc(Row);                            // =NPER(3%/12, -150, 5000)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=NPER(3%%/12%s -150%s 5000)', [ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(3.5,
+    RPNNumber(3,
     RPNFunc(fekPERCENT,
     RPNNumber(12,
     RPNFunc(fekDIV,
@@ -1818,10 +1833,10 @@ begin
   // paid off in 2 years (ie: 2 x 12). All payments are made at the beginning
   // of the period.
   // Adapted from //www.techonthenet.com/excel/formulas/pmt.php
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=PMT(3.5%/12,2*12,5000,0,1)');
+  inc(Row);                            // =PMT(3%/12, 2*12, 5000, 0, 1)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=PMT(3%%/12%s 2*12%s 5000%s 0%s 1)', [ls, ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(3.5,
+    RPNNumber(3,
     RPNFunc(fekPERCENT,
     RPNNumber(12,
     RPNFunc(fekDIV,
@@ -1862,8 +1877,8 @@ begin
   Worksheet.WriteNumber(Row, 2, ord(SHelloWorld[1]));
 
   // Left part of string
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, Format('=LEFT("%s",3)', [SHelloWorld]));
+  inc(Row);                            // =LEFT("%s", 3)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=LEFT("%s"%s 3)', [SHelloWorld, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString(SHelloWorld,
     RPNNumber(3,
@@ -1872,8 +1887,8 @@ begin
   Worksheet.WriteUTF8Text(Row, 2, Copy(SHelloWorld, 1, 3));
 
   // Mid part of string
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, Format('=MID("%s",4,5)', [SHelloWorld]));
+  inc(Row);                            // =MID("%s", 4, 5)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=MID("%s"%s 4%s 5)', [SHelloWorld, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString(SHelloWorld,
     RPNNumber(4,
@@ -1883,8 +1898,8 @@ begin
   Worksheet.WriteUTF8Text(Row, 2, Copy(SHelloWorld, 4, 5));
 
   // Right part of string
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, Format('=RIGHT("%s",3)', [SHelloWorld]));
+  inc(Row);                            // =RIGHT("%s", 3)
+  Worksheet.WriteUTF8Text(Row, 0, Format('=RIGHT("%s"%s 3)', [SHelloWorld, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString(SHelloWorld,
     RPNNumber(3,
@@ -1923,14 +1938,14 @@ begin
   inc(Row);
   Worksheet.WriteUTF8Text(Row, 0, Format('=PROPER("%s")', [uppercase(SHelloWorld)]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNString(SHelloWorld,
+    RPNString(Uppercase(SHelloWorld),
     RPNFunc(fekPROPER,
     nil))));
   Worksheet.WriteUTF8Text(Row, 2, 'Hello World!');
 
   // replace
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, Format('=REPLACE("%s",7,5,"Friend")', [SHelloWorld]));
+  inc(Row);                            // =REPLACE("%s", 7, 5, "Friend")
+  Worksheet.WriteUTF8Text(Row, 0, Format('=REPLACE("%s"%s 7%s 5%s "Friend")', [SHelloWorld, ls, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString(SHelloWorld,
     RPNNumber(7,
@@ -1943,8 +1958,8 @@ begin
   // substitute
   // Note: the function can have an optional parameter. Therefore, you have
   // to specify the actual parameter count.
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, Format('=SUBSTITUTE("%s","l",".")', [SHelloWorld]));
+  inc(Row);                            // =SUBSTITUTE("%s", "l", ".")
+  Worksheet.WriteUTF8Text(Row, 0, Format('=SUBSTITUTE("%s"%s "l"%s ".")', [SHelloWorld, ls, ls]));
   Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
     RPNString(SHelloWorld,
     RPNString('l',
@@ -1957,53 +1972,44 @@ begin
   Worksheet.WriteUTF8Text(Row, 0, 'Errors');
   Worksheet.WriteUsedFormatting(Row, 0, [uffBold]);
 
-  // Division by 0
+  if IncludeErrors then begin
 
   // These tests partly produce an error messsage when the file is read by Excel.
   // In order to avoid confusion they are deactivated by default.
   // Remove the comment below to see these tests.
 
-                    (*
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=1/0');
-  Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(1,
-    RPNNumber(0,
-    RPNFunc(fekDiv,
-    nil)))));
-  Worksheet.WriteUTF8Text(Row, 2, 'Error #DIV/0!');
+    inc(Row);
+    Worksheet.WriteUTF8Text(Row, 0, '=1/0');
+    Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+      RPNNumber(1,
+      RPNNumber(0,
+      RPNFunc(fekDiv,
+      nil)))));
+    Worksheet.WriteUTF8Text(Row, 2, 'Error #DIV/0!');
 
-  // Not enough operands  for operation
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=1/2 ("2" forgotten from formula)" ');
-  Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(1,
-    // here we'd normally put "RPNFormula(2," - but we "forget" it...
-    RPNFunc(fekDiv,
-    nil))));
-  Worksheet.WriteUTF8Text(Row, 2, 'Error #N/A"');
+    // Not enough operands  for operation
+    inc(Row);
+    Worksheet.WriteUTF8Text(Row, 0, '=#N/A');
+    Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+      RPNNumber(1,
+      // here we'd normally put "RPNNumbe(2," - but we "forget" it...
+      RPNFunc(fekDiv,
+      nil))));
+    Worksheet.WriteUTF8Text(Row, 2, 'Error #N/A"');
+    Worksheet.WriteUTF8Text(Row, 3, 'Should be "=1/2", but the "2" is forgotten from the formula...');
 
-  // Too many operands given
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=1/2 (too many operands)');
-  Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(1,
-    RPNNumber(2,
-    RPNNumber(3,       // This line is too much
-    RPNFunc(fekDiv,
-    nil))))));
-  Worksheet.WriteUTF8Text(Row, 2, 'Error #N/A!');
-
-  // Parameter count not specified
-  inc(Row);
-  Worksheet.WriteUTF8Text(Row, 0, '=SUM(1, 2) (parameter count not specified');
-  Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
-    RPNNumber(1,
-    RPNNumber(2,
-    RPNFunc(fekSum,  // We "forget" to specify the number of arguments
-    nil)))));
-  Worksheet.WriteUTF8Text(Row, 2, 'Error #N/A');
-                       *)
+    // Too many operands given
+    inc(Row);
+    Worksheet.WriteUTF8Text(Row, 0, '=#N/A');
+    Worksheet.WriteRPNFormula(Row, 1, CreateRPNFormula(
+      RPNNumber(1,
+      RPNNumber(2,
+      RPNNumber(3,       // This line is too much
+      RPNFunc(fekDiv,
+      nil))))));
+    Worksheet.WriteUTF8Text(Row, 2, 'Error #N/A!');
+    Worksheet.WriteUTF8Text(Row, 3, 'Should be "=1/2", but there are too many operands...');
+  end;
 end;
 
 end.
diff --git a/components/fpspreadsheet/xlsbiff2.pas b/components/fpspreadsheet/xlsbiff2.pas
index cace0eeb2..503944a22 100755
--- a/components/fpspreadsheet/xlsbiff2.pas
+++ b/components/fpspreadsheet/xlsbiff2.pas
@@ -521,8 +521,76 @@ begin
 end;
 
 procedure TsSpreadBIFF2Reader.ReadFormula(AStream: TStream);
+var
+  ARow, ACol: Cardinal;
+  XF: Word;
+  ok: Boolean;
+  formulaResult: Double;
+//  rpnFormula: TsRPNFormula;
+  Data: array [0..7] of byte;
+  dt: TDateTime;
+  nf: TsNumberFormat;
+  nd: Byte;
+  ncs: String;
+  nfs: String;
+  err: TsErrorValue;
+  cell: PCell;
 begin
+  { BIFF Record row/column/style }
+  ReadRowColXF(AStream, ARow, ACol, XF);
 
+  { Result of the formula result in IEEE 754 floating-point value }
+  AStream.ReadBuffer(Data, Sizeof(Data));
+
+  { Recalculation byte - currently not used }
+  AStream.ReadByte;
+
+  // Now determine the type of the formula result
+  if (Data[6] = $FF) and (Data[7] = $FF) then
+    case Data[0] of
+      0: // String -> Value is found in next record (STRING)
+         FIncompleteCell := FWorksheet.GetCell(ARow, ACol);
+      1: // Boolean value
+         FWorksheet.WriteBoolValue(ARow, ACol, Data[2] = 1);
+      2: begin  // Error value
+           case Data[2] of
+             ERR_INTERSECTION_EMPTY   : err := errEmptyIntersection;
+             ERR_DIVIDE_BY_ZERO       : err := errDivideByZero;
+             ERR_WRONG_TYPE_OF_OPERAND: err := errWrongType;
+             ERR_ILLEGAL_REFERENCE    : err := errIllegalRef;
+             ERR_WRONG_NAME           : err := errWrongName;
+             ERR_OVERFLOW             : err := errOverflow;
+             ERR_ARG_ERROR            : err := errArgError;
+           end;
+           FWorksheet.WriteErrorValue(ARow, ACol, err);
+         end;
+      3: // Empty cell
+         FWorksheet.WriteBlank(ARow, ACol);
+    end
+  else begin
+    if SizeOf(Double) <> 8 then
+      raise Exception.Create('Double is not 8 bytes');
+
+    // Result is a number or a date/time
+    Move(Data[0], formulaResult, SizeOf(Data));
+
+    {Find out what cell type, set content type and value}
+    ExtractNumberFormat(XF, nf, nd, ncs, nfs);
+    if IsDateTime(formulaResult, nf, dt) then
+      FWorksheet.WriteDateTime(ARow, ACol, dt, nf, nfs)
+    else
+      FWorksheet.WriteNumber(ARow, ACol, formulaResult, nf, nd, ncs);
+  end;
+
+  { Formula token array }
+  if FWorkbook.ReadFormulas then begin
+    cell := FWorksheet.FindCell(ARow, ACol);
+    ok := ReadRPNTokenArray(AStream, cell^.RPNFormulaValue);
+    if not ok then FWorksheet.WriteErrorValue(cell, errFormulaNotSupported);
+  end;
+
+  { Apply formatting to cell }
+  ApplyCellFormatting(ARow, ACol, XF);
 end;
 
 procedure TsSpreadBIFF2Reader.ReadLabel(AStream: TStream);
diff --git a/components/fpspreadsheet/xlscommon.pas b/components/fpspreadsheet/xlscommon.pas
index 87eab0a64..ef92088a0 100644
--- a/components/fpspreadsheet/xlscommon.pas
+++ b/components/fpspreadsheet/xlscommon.pas
@@ -325,7 +325,7 @@ const
   ERR_ILLEGAL_REFERENCE                  = $17;  // #REF!
   ERR_WRONG_NAME                         = $1D;  // #NAME?
   ERR_OVERFLOW                           = $24;  // #NUM!
-  ERR_NOT_AVAILABLE                      = $2A;  // #N/A
+  ERR_ARG_ERROR                          = $2A;  // #N/A (not enough, or too many, arguments)
 
 type
   TDateMode=(dm1900,dm1904); //DATEMODE values, 5.28
@@ -516,8 +516,8 @@ const
     // Basic operations
     INT_EXCEL_TOKEN_TADD,           {fekAdd, +}
     INT_EXCEL_TOKEN_TSUB,           {fekSub, -}
-    INT_EXCEL_TOKEN_TDIV,           {fekDiv, /}
     INT_EXCEL_TOKEN_TMUL,           {fekMul, *}
+    INT_EXCEL_TOKEN_TDIV,           {fekDiv, /}
     INT_EXCEL_TOKEN_TPERCENT,       {fekPercent, %}
     INT_EXCEL_TOKEN_TPOWER,         {fekPower, ^}
     INT_EXCEL_TOKEN_TUMINUS,        {fekUMinus, -}
@@ -1051,10 +1051,8 @@ var
   ARow, ACol: Cardinal;
   XF: WORD;
   ResultFormula: Double;
-  RPNFormula: TsRPNFormula;
-  Data: array [0..7] of BYTE;
+  Data: array [0..7] of byte;
   Flags: WORD;
-//  FormulaSize: BYTE;
   i: Integer;
   dt: TDateTime;
   nf: TsNumberFormat;
@@ -1062,7 +1060,7 @@ var
   ncs: String;
   nfs: String;
   resultStr: String;
-  err: TErrorValue;
+  err: TsErrorValue;
   ok: Boolean;
   cell: PCell;
 
@@ -1072,7 +1070,7 @@ begin
   { Index to XF Record }
   ReadRowColXF(AStream, ARow, ACol, XF);
 
-  { Result of the formula in IEE 754 floating-point value }
+  { Result of the formula result in IEEE 754 floating-point value }
   AStream.ReadBuffer(Data, Sizeof(Data));
 
   { Options flags }
@@ -1081,20 +1079,6 @@ begin
   { Not used }
   AStream.ReadDWord;
 
-  { Formula size }
-     (*
-  FormulaSize := WordLEtoN(AStream.ReadWord);
-
-  { Formula data, output as debug info }
-{  Write('Formula Element: ');
-  for i := 1 to FormulaSize do
-    Write(IntToHex(AStream.ReadByte, 2) + ' ');
-  WriteLn('');}
-
-  //RPN data not used by now
-  AStream.Position := AStream.Position + FormulaSize;
-       *)
-
   // Now determine the type of the formula result
   if (Data[6] = $FF) and (Data[7] = $FF) then
     case Data[0] of
@@ -1112,7 +1096,7 @@ begin
              ERR_ILLEGAL_REFERENCE    : err := errIllegalRef;
              ERR_WRONG_NAME           : err := errWrongName;
              ERR_OVERFLOW             : err := errOverflow;
-             ERR_NOT_AVAILABLE        : err := errArgNotAvail;
+             ERR_ARG_ERROR            : err := errArgError;
            end;
            FWorksheet.WriteErrorValue(ARow, ACol, err);
          end;