History:
In my custumtag i had musicians separated by ";".
I choose to save this tag to the 'involvedpeople' tag in the mp3 file.
Then the problems in the previuos posts occured.
In MP3tag i saw that i had name:name;name:name.
I tried to replace the ':' with ';'.
I got name:;name:;name:;.
I learned involved people is the name and the type of involvement.
I did not find this but i guess it is name:involvement;name:involvement and so on.
So i replaced all ':' tesulting in ':;' meaning no type of involvement.
Reinstalled MB.
New library.
custom one sored in the file in involved people.
Problem
MB shows name:name;name:name
While i hoped for name:;name:;name:;