Hi,
Maybe it's just an easy tag write/read option I missed...
- Tagged mp3s in MP3Tag (ID3v1, ID3v2.4 (UTF-8), APE) incl. Cover
- Imported them into iTunes
- Edited any tag info (e.g. change genre) within iTunes
- Imported same mp3-files back into MP3Tag (e.g. to change cover again etc.)
--> MP3Tag won't read ID3v2 or APE info displayed, only ID3v1 (although option set to read ID3v1, v2 AND APE)
--> Importing same files into Picard shows that v2 info still exists
--> However, after saving the mp3-files in MP3Tag (with only the ID3v1 info read and displayed), then the files in fact only have ID3v1 tags, no more ID3v2 info.
This issue makes it impossible to continue using MP3Tag for any re-editing once iTunes has been used for any tagging.
In which way does iTunes change the tags so that other tagging software (e.g. Picard) can still find ID3v2 info, but MP3Tag can't?!
Depending on iTunes because of iPod 
Looking further into iTunes alternatives... grrr