With that setup bob you Hit/hold the line lock THEN hit the brakes and hold them. What you are doing is
blocking brake fluid travel to the rear brakes. So if what you are doing is holding the brakes,
then hitting the button, then letting off the brakes....basically you just locked your rear brakes, and have no pressure on the front calipers at all. Which if you can even break the tires loose, its going to roll.
Like i said you need to flip the switch (basically cuts out the rear brakes), then apply the front brakes (brake pedal) THEN hit the throttle...That gives you the ability to let up on the brake pedal some and do some nasty rolling burnouts.
...itll work...If you still have issues, head on over this weekend, i'll video