Dear Florian -
I've been out on summer vacation; when I returned, another great release! I've really enjoyed 2.12 and it's gone through many mp3s.
I've got an idea that could be considered: since the ID3 Version 2 tags are pretty fluid in structure (by design), other programs sometimes insert proprietary information. Is there any way to implement a "Remove Extraneous Tags?"
P.S. - I would be happy to offer my services as a translator for the manual or in any other capacity in regards to the program. Please let me know; I'll be honored to help.