He aquí la solución al final. Ya funciona perfectamente y esas cosas.

Si no se entiende, la explicaré (lo cual no dice que sea la mas óptima y la mas eficiente y la mas bonita y... pero me la he currao como he podido)

Código Delphi [-]
procedure TfGlobal.CalcularStarCross;
var
  CharSelected: string;
begin
  sStartCross := '';
  buffer := BuildIniFile.ReadString('XREFER_PARAMETERS', TempList.Strings[1], ''); //Leo el sStarCross del INI
  CharSelected := AnsiLeftStr(buffer, 1);
  buffer := AnsiRightStr(buffer, Length(buffer) - 1);

  repeat
    if (CharSelected <> ',') and (CharSelected <> '[') and (CharSelected <> ']') and (CharSelected <> Chr(39)) then
      begin
        buffer2 := buffer2 + CharSelected;
        CharSelected := AnsiLeftStr(buffer, 1);
        buffer := AnsiRightStr(buffer, Length(buffer) - 1);
      end
    else
      if (CharSelected = ',') then
        begin
          sStartCross := sStartCross + Chr(StrToInt(buffer2));
          CharSelected := AnsiLeftStr(buffer, 1);
          buffer := AnsiRightStr(buffer, Length(buffer) - 1);
          buffer2 := '';
        end
      else
        begin
          CharSelected := AnsiLeftStr(buffer, 1);
          buffer := AnsiRightStr(buffer, Length(buffer) - 1);
        end;
  until CharSelected = ']';

  sStartCross := sStartCross + Chr(StrToInt(buffer2));
  CharSelected := AnsiLeftStr(buffer, 1);
  buffer := AnsiRightStr(buffer, Length(buffer) - 1);
  buffer2 := '';
end;

Después de esta, paso a "Novato en Delphi 88%"