I noticed recently my gamma setting stuck. It doesn't matter how I set the gamma slider in video options, my gamma setting is at certain value all the time.
It use to work when I installed the game, but now it seems to be stuck.
I don't know if it's related, but I noticed this problem after I've installed and FacerackNoIR head tracking software. Still, it doesn't matter if the program is running or not, gamma slider doesn't work. {F18199} {F18200} {F18201}
I have a similar problem (might be identical). If I set Gamma to a non-default value it generally won't have taken effect when I first start the game (I've only used the editor so far).
However if I then open and close the video options dialog 3 out of 4 times it will take effect immediately upon closing the dialog (even if I use Cancel to close it). The rest of the time (roughly 1 in 4) the Gamma setting refuses to apply no matter how many times I open and close Video Options.
My card is an AMD HD6950 using Catalyst 13.3.
According to the changelog, this was fixed.
If the issue is still reproducable for you, please create another ticket requesting this one be re-opened.