http://bugs.winehq.org/show_bug.cgi?id=11057
--- Comment #11 from Tobias Jakobi liquid.acid@gmx.net 2008-07-17 15:40:21 --- You don't need input to verify this. Just start a random level, the effect is visible at once.
The bug isn't dependent von graphics card, it appears both on my Intel and the GeforceFX. Probably the demo is based on the original engine version.
This bug doesn't appear with version 1.0 of B2. You first need to patch it to version 2.1 to make it appear.
Greets, Tobias