Just give it time, these forums are pretty slow moving. We're pretty much all hobbyists on the forums, I think. As to your question, I don't quite know, sorry. I'm not very experienced personally.
I did run into a possibly similar problem when I used a model that I didn't make as a test. The collision box was not matched to the mesh correctly. (the box was the right size, but centered around the bottom of the mesh) when I used a model I made myself, the box lined up right. I suspect that the box was created around the editable location known as the "center" of the model (center of mass?), but I could be barking up the wrong tree entirely. I know when I made my own test model, I didn't change that center, and built the model about the origin (I used blender), anyways.
Also, keep in mind that I used a different toolchain, irrlicht+irrBullet. Your milage may vary, some conditions apply.
Seriously though, I hope this helps.
Also, if this doesn't help, try posting your question in the feedback forum. It seems that is the most active forum for support.