ive been trying to increase rayman forever's resolution and enable hq3 to make it look better but when i adjust the settings in the graphic mode setup tool i just get a "game not installed" error when i try to save my changes or even launch the game from the setup menu. does anyone know how to fix this or change these settings another way?

run the graphics setup from the start menu - it requires parameters.
"C:\Program Files\GOG.com\Rayman Forever\Graphic mode setup.exe" GOGRAYMAN1