For the decorators try putting this in your Screen section in xorg.conf: Option "AddARGBGLXVisuals" "true"
For the missing windows this happens when you run out of texture memory (driver bug) or when you start compiz with a minimized window (compiz bug).
The cube thing is a separate bug, already filed.
As for the speed, compiz screams on my GeForce Go 7400.
With all that in mind, I believe this is a configuration error and not a bug.
For the decorators try putting this in your Screen section in xorg.conf:
Option "AddARGBGLXVisuals" "true"
For the missing windows this happens when you run out of texture memory (driver bug) or when you start compiz with a minimized window (compiz bug).
The cube thing is a separate bug, already filed.
As for the speed, compiz screams on my GeForce Go 7400.
With all that in mind, I believe this is a configuration error and not a bug.