All visible things of the program, like menues, dialogs, text, bitmaps, cursors, ... are loaded from the programs resources. The german defaults are statically in the EXE file. The program looks for a DLL(dynamic link library) with the name 'udiwre01.dll' and will load all resources from this file. You can configure the name of the DLL in the 'Optionen Einstellungen Sonstige' Dialog as well. If the DLL does not work, start the program with the '-r' option.
This DLL is included in the english files above (udiw1e08.exe).
The Source of the DLL is available here: 360437 Apr 9 16:46 udiwres.exe
If somebody wants to translate the resources into another language, he can do this now. (And send it back to me).
I could use some nicer bitmaps. Is there someone, how wants to design some nice bitmaps?