Orange Power Light
If you start a program and your iMac's monitor shuts off with an orange power light, it means the Game Wizard card has been activated but isn't working properly. The iMac Game Wizard can only run at a screen resolution of 640 by 480 or 800 by 600. Running OpenGL programs it can only run at 640 by 480. If a program tries to use any other resolution the monitor can't detect a video signal and automatically goes to sleep.
If this happens, press command-option-S.
This switches the video output back to the original video chip
and will hopefully allow you to change the settings or quit the
program. Pressing command-option-S again will switch back to
the Game Wizard.
Games Too Dark
If the screen is too dark you may need to change the gamma setting. First check the game's own options to see if the brightness or gamma can be increased. If that doesn't help try putting a voodoo2.ini or voodoo2.var file with a gamma setting in the game's folder. The table below lists some games I've tested and the gamma settings I used. Games listed as using Glide will look for a voodoo2.ini file, those using Glide 3 or OpenGL will look for a voodoo2.var file. If you're unsure, just put both files in the game's folder.