How about a example of your movement-script or a link where we can download the level. A7 has a integrated collision detection system so you won't need to write your own.
I'm using a base from the Kingdom hearts movement tut. and the level is simply 4 block 1 for a floor and the other 3 make a u-shaped colvert. it seems if I hit the block in the right place I get stuck. I don't have a a web page to upload a demo of the level to and it be a little to big to e-mail...