I've downloaded and am trying 'MP3-Tag Studio 3', and am pretty happy with it. I am concerned , though, because it's banner ad supported.
I'm adding ID3V2 tags to all of my self-made mp3's to get the best label info to show up in WinCAB. Basically, I"m copying the ID3V1 and adding the letters back that V1 tags chop off (30 character limit in the V1 tags for most fields). Then I'm changing the name of the .mp3 file itself to match the full name with a track number in front of the name, since all my files are from albums that I own.
I tried using WinAMP's built-in tag editor, which does have a 'copy from ID3V1' function, and that seemed to work. The longer names were showing up in WinCAB. But when I went back into WinAMP to make a slight change again there was NO INFO in the ID3V1 or ID3V2. Using MP3-Tag Studio 3 is working and both tags then show up in WinAMP's editor. Bizzare.