ID3 Data

[glup]

I have some problems with ID3 data when editing the Tags of my tracks. To have the data complete and at the right places is important for interoperability:

1. Where do I enter TPOS ('Part of a set') data? I have many compilations with more than one CD and I do of cause not put the disk into the album title.
2. Where do I enter the number of tracks of a CD? I'm refering to the second number in the TRCK ('Track number/Position in set') frame.
3. ID3 allows 3 Title Fields (TIT1, TIT2 and TIT3). How could I edit them with MM?
4. Where do I store the Original Release Date (TORY resp. TDOR)? It is an important information for compilations.

Thx for Help!