when i start nexuiz on mac osx the white balance or brightness is extremely high. It is so high that i cant even read the text for settings, and therefore i cant change the white balance.

computer is a imac w/ a 256 mb vram gcard( dont exactly know what model, i think its a ati)
does it in both sdl and normal.
nexuiz ver 2.5.2

is there a way that i can edit a file to change this?

yes, the file is ~/.nexuiz/data/config.cfg. Just try renaming the file for a first test.