1) Yes. Or if that was a strangely worded question, maybe you asked for this:
http://www.epforums.org/showthread.p...-name-of-games
2) A higher number is a newer build, and probably has more roms added and more verified (!) CRCs.
3) Yes. Although the possibility of new releases exists.
4) I'm sure it's just compressed differently. But if you ever think a goodset you've downloaded isn't complete, you can easily just run it past it's goodtool yourself.