Replying to BINDING HELP!!!!

I have recently purchased a pair of saloman chaos boots from my local store and i figured they would be easy to mount to my PE's but they were not. The shell of the boot is a little bigger than my old boot so i slid the heel of the binding back but my boot popped out way to easily. So i had to adjust it on the mountain and i pushed the heel forward making it a tighter fit to my boot (maybe to tight). Just ridding around and what not i am fine, but when i hit jumps and do nose blocks I have some trouble. I don't know what to do. HELP!!