If you get it working with the liveCD, you can just copy it over to hd:
boot liveCD with the cheatcodes that work
open a console
sudo su
mount /mnt/hd?? (your linux install partition being ??)
mount -t ext3 -o remount,rw /dev/hd?? /mnt/hd?? (if already mounted of you need to specify filesystem, choose to needed options)
mv /mnt/hd??/etc/X11/XF86Config-4 /mnt/hd??/etc/X11/XF86Config-4_OLD1
cp /etc/X11/XF86Config-4 /mnt/hd??/etc/X11/XF86Config-4
ctrl-d
reboot to hd install