I had email contact with Allround Automations and this is the result:
(Correct me when wrong)
1) When your application needs to run against a Unicode Database, but your application is not Unicode ready, you can set the global variable NoUnicodeSupport to True. => This works at my site
2) This is of course a Runtime only solution.
So they will add a cuUTFToLocal option in the preferences in the next patch release.
So I have set the preferences back to cuNone and set the NoUnicodeSupport to True and everything works again flawlessly.