Use lighting commands, look in DarkSDKLight.h, if you installed in the default location it should be something like c://programfiles/the game creators/include/DarkSDKLight.h
also, check in DarkSDKDisplay.h, it has commands that allow you to manipulate the settings on the monitors, I didnt check but i can only assume contrast and gamma are incorporated as well.
Check in c://program files/the game creators/documentation/DarkGDK.chm , for in-depth information about any of the commands you have questions about.
EYE R T3H +ick +ack +oe mester