Hi Uwe,
The problem with unwanted date formats has nothing to do to Excel, InDesign or the script. This happens because you have "Non English" settings in your System. I had the same issue with my Russian system too. If you change comma to dot in the "decimal separator" (not sure if that's correct translation) field, it should work as expected.
On Windows, it should be changed here:
There’s an analogous setting on Mac but I don’t remember which exactly (I don’t have a Mac at hand at the moment).
Try to do the following:
1. Change temporarily your "Language & Text" settings from German to English
2. Run the script and choose "Tab" for delimiters and "CSV" for file extension
3. Open the csv-file in Excel
I can test it with German characters on Mac later today when I get to work.
There is significant distinction between different versions of Excel on both platforms (the way they import csv/txt files). I made options for selecting a delimiter and file type to make sure that at least one combination of the settings works for every version.
Regards,
Kasyan