This is an Altium DelphiScript that creates pin functions from a CSV file.

CSV2Functions.pas

// Convert CSV to Altium pin functions.
// Contributors: Chris Harrison, René HENKE

Procedure CSV2Functions;
Var
    SchLib: ISch_Lib;
    SchComponent: ISch_Component;

    OpenDialog: TOpenDialog;
    PinList: TStringList;
    PinEntry : string;

    CSVFile: File;
    CSVLine, PinName, PinPropList, PinFunctions: string;
    i, j, DelimiterPosName, DelimiterPosFct, DelimiterPos: Integer;

    PinIterator: ISch_Iterator;
    PinItem: ISch_Line;

    NoOfEntrys : Integer;
Begin
    // Get current document
    SchLib := SchServer.GetCurrentSchDocument;

    if SchLib = Nil Then
    begin
         ShowError('Script must be run from an SchLib document.');
         Exit;
    end;

    if (SchLib.ObjectID <> eSchLib) Then
    begin
         ShowError('Document is not an SchLib.');
         Exit;
    end;

    SchComponent := SchLib.CurrentSchComponent;

    if SchComponent = nil then
    begin
      ShowError('No schematic symbol currently open.');
      Exit;
    end;

    // Prompt for CSV file
    OpenDialog := TOpenDialog.Create(nil);

    try
        OpenDialog.Filter := 'CSV Files|*.csv|All Files|*.*';
        OpenDialog.Title := 'Select CSV File';

        if not OpenDialog.Execute then
        begin
            ShowError('No CSV file selected.');
            Exit;
        end;

        // Initialize the pin list
        PinList := TStringList.Create;

        try
            // Open CSV file
            try
                AssignFile(CSVFile, OpenDialog.FileName);
                Reset(CSVFile);
            except
                Raise('Error opening file: ' + OpenDialog.FileName);
            end;

            // Parse CSV
            while not Eof(CSVFile) do
            begin
                Readln(CSVFile, CSVLine);

                DelimiterPos := Pos(',', CSVLine);

                if DelimiterPos > 0 then
                begin
                    // Append to lis
                    PinList.Add(AnsiReplaceText(CSVLine, ',', '/'));
                end;
            end;

            // Close the CSV file
            CloseFile(CSVFile);

            // Iterate through component pins
            PinIterator := SchComponent.SchIterator_Create;
            PinIterator.AddFilter_ObjectSet(MkSet(ePin));

            PinItem := PinIterator.FirstSchObject;
            while PinItem <> Nil Do
            begin
                // PinItem.Name
                PinName := PinItem.GetState_Designator;

                for j := 0 to PinList.Count - 1 do
                begin
                    PinEntry := PinList[j];
                    if StartsText(PinName + '/', PinList[j]) then
                    begin
                        DelimiterPosName := Pos('/', PinList[j]);
                        PinPropList := Copy(PinList[j], DelimiterPosName + 1, Length(PinList[j]) - DelimiterPosName);
                        DelimiterPosFct := Pos('/', PinPropList);
                        PinName := Copy(PinPropList, 1, DelimiterPosFct-1);
                        PinFunctions := Copy(PinPropList, DelimiterPosFct + 1, Length(PinPropList) - DelimiterPosFct);

                        if AnsiEndsStr('/', PinFunctions) then
                            PinFunctions := Copy(PinFunctions, 1, Length(PinFunctions) - 1);

                        PinItem.SetState_Name(PinFunctions + '/');
                        PinItem.SetState_FunctionsFromName;
                        PinItem.SetState_Name(PinName);
                        PinItem.GraphicallyInvalidate;

                        break;
                    end;
                end;

                PinItem := PinIterator.NextSchObject;
            end;

            SchComponent.SchIterator_Destroy(PinIterator);

            SchLib.GraphicallyInvalidate;

            SchServer.ProcessControl.PreProcess(SchLib, '');
            SchServer.ProcessControl.PostProcess(SchLib, '');

            ShowMessage('Pin functions updated successfully.');
        finally
            PinList.Free;
        end;
    finally
        OpenDialog.Free;
    end;
End;

Hi There,
I forked your script and made a lots of comments to make it more understandable.
Also I made it so that if there is only one Function behind the designator it will take that for the name and adds no functions. before it was that it will add no name and one function.
Sadly i did not figure out how to clear all functions (have none, if there was one before) it can only overwrite all of them, if you add at least a single new one... sucks...
I love the PIN functions, but is so badly implemented :(

Feel free to use the changed one on your site :-)