Quote: "Sometimes a texture gets replaced by an odd dark-grey arrow on a grey button??? (looks like a window button)"
Don't know about that. Never happened to me before, although I had transparency problems on an Radeon 9000.
Quote: "When I set "sync rate 60" my fps drops to 40, but when I set "sync rate 0" I get 60 fps :S (try it, if you have it set to 60)
"
My FPS can go up to as high as 99 when I use sync rate 0. Yep, mine also stays at 40 when I use sync rate 60. My PC is slower than yours though (p4 1.5 ghz, 384mb rdram, geforce2mx 32mb). Maybe it's the polycount of your program?
Quote: "When I use a midi, the fps will drop to 7~12 when it's finished playing (a loop in the interpreter?)"
Has something to do with the loop music command. It happens on mine no matter what format I use. I'm not sure if using stop music then play music instead will help it though.

"Story in a game is like story in a porn movie. It's expected to be there, but it's not that important." - John Carmack