You may also want to consider adding the command "xhost +"
I know to launch my SmartCoin on the Prefinal from ssh I have to run the following
DISPLAY=:0 xhost +
DISPLAY=:0 sudo smartcoin
Otherwise SmartCoin will error
here's a safer way lol it was already on the wiki

sudo su
chmod uog+rw /dev/ati/card*
xauth merge /home/user/.Xauthority
export DISPLAY=:0
smartcoin
will all of those commands need to be run after each reboot or will the chmod and xauth part stick around? I am using persistence on this setup