Unfortunately, I am going to be running XP for a while. I won't have opportunity to upgrade anytime soon. In any case, a patch for CM: GM Edition on XP is probably unrealistic, since support for XP was discontinued a few years ago, I believe.
By the way, I am pretty sure I just discovered another bug, an extension of #4, above. When I win, it adds points to my overall rating, but when I lose, it subtracts points from my specific rating... I think. Something like:
Scenario: win
1507 + 17 = 1524 (overall)
1507 + 36 = 1524 (standard)
Scenario: lose
1650 - 21 = 1620 (overall)
1650 - 30 = 1620 (standard)
So, it's inconsistent in the type of rating it adjusts after a game (based on win v. loss), in addition to simply making arithmetic errors. Does this explanation make sense?
Really? I have Windows XP and it works fine. The bugs don't really matter as long as it is not something like causing Chessmaster to freeze and crash (which actually did happen, but shouldn't happen again.)