I'm not familiar with running the live CD
So you should not answer.
You may need to run with the vesa driver.
A proper xorg.conf was missing. I needed to create one with: X -configure
Then I used it with:
X -config /root/xorg.conf.new
export DISPLAY=:0.0
gnome-session
and now I'm root inside Firefox.
Could someone fix the appropriate script?