I'm really not sure what that file is for, but I know that I manually changed my video settings by modifying /etc/X11/X86Config file and it worked. I took a look at the X86Config-4 file, it looks like a good bet too, but all I know is that my changes took effect from only the X86Config file changes.

Just out of curiosity, why aren't you using the Control Centre X11 Display options? If you're trying to run them and everytime the app simply fails, remember that you have to be running kcontrol (the Control Centre) as root. There simply isn't a passwd prompt from the Display options (unfortunately).

Good Luck,

Civ