I think u can solve this problem, by using physics engine of the 3dgs. Use Ph_Poly or Ph_Polygon and assign it in the action script to the model of the corridor. I hope it helps u.
I am thinking you have a problem with your geometry..
On the walls to the left and right are divided into 4 parts(the big "X" shape) make sure there is a vertex in the center, other wise you have overlaping and possibly problems with normals....also move your "ball" to the opposite side of where you have a collision issue and look at the collision area(it may be a polygon with a flipped normal)...and of course check your normals. Are you setting the polygon flags(polly collision)if not it can also be th bounding box you are colliding with....?
Sorry for the duplicate, ia solved this yes, i curved the geometry alittle, the screenshot is just an attemp to tesselate the mesh and make it tri's. But its working now with optimised quads. Thanks for the input folks :-)