Thanks mohoc for the deep explanation! I guess it should be working now!

Thanks, but there is a part in Lab where you flippin' between two lines. At the beginning of that you can just hold left, and pass it until the second green background part. Now I can't do that. I guessed that is because of the 29 fps.

Earlier the game could run at 30fps but now with the same settings it is only running at 29fps in windowed. Can anybody help me?