First of all you need a good paint program that can handle PSD files.
I've used Paint Shop Pro 7 (you can get a demo with full functionality at www.jasc.com
) but this description should apply to all paint programs.
There are 16 colors - for your convenience I've listed each color field with its horizontal (X) position, its color and a description of functionality:
Fields without description are most likely useless and should be ignored.
Now select the paint brush and turn its size down to the minimum value so it can paint single pixels.
Then paint whatever you like into these fields and save the result overwriting the file you just opened (you kept a backup, didn't you?) and restart GSA.
I personally recommend to put the color of registered and "away" users (maybe also the color of VIPs and admins) to the color of normal users 'cuz all the colors all the time are too annoying.
The link color can be set within the Gamespy chat configuration - that's why it's not listed here.