Thank you, Jason, that fixed this problem.
The other problem I mentioned occurred on the pages I generated for tblname2 (also a language relevant tbl). On those pages I selected a record in polish and deleted it (right on the result page), but it deleted not only the polish record, but the records with the same id for all other languages. I did not mean it deleted records in other tables.
I think this will happen again, also with tblversion, because when I click on the version id to open the detail page, it will open the german record, not the language that was displayed when I clicked on the version id.
What baffles me is, that I used the same wizard to generate pages for another, also language relevant table. And with those pages I have no problems. It opens the detail page in the chosen language and only updates that language.
