Collision with avatars and scene not working

[JvdBosch]

Hi!

I import a scene from OSG (.ive file) into Vizard 3.0 and want to have avatars walking around in it. I have it working, but it takes to much calculation time, so I'm trying to make it better. It works fine with viz.intersect (calculating an intersection between the avatar and x meter in front of it), but I would like to use physics (hoping it would bet easier on the CPU).
I tried this method:
I assigned a collidemesh to the objects of the imported scene, which I want the avatars to collide with. The avatars have an avatar.collidebox around them, with the collision notify on.
I assigned an event which is triggered by a collision (like in the tutorial). But the avatar does not collide with the scene....

What am I doing wrong??
Any ideas??