One of the improvements of the recent released alpha version of the engine (read the original post to download the preview) is related to the collision of ODE (Open Dynamics Engine) rigid body objects and the BSP (binary space partition) geometry. Now balls and other bodies bounce perfectly alsp in BSP levels.
To see the feature at work, execute the demo "BallsOnTriMesh.lua" available in DemoPack1. The demo is divided in 4 sections performing collision of two meshes (ball shaped) against a mesh, a height-field, patches (infinite terrain) and a BSP level. Finally, also the latter works perfectly, so users can simulate the dynamics of ODE objects in complex indoor environments.