Irrlicht Engine

Hi! I was trying to modify the Per pixel lighting demo, so it would use a scene mesh optimized by an OctTree instead of non-optimized. So I just changed "addMeshSceneNode" to "addOctTreeSceneNode", but it builds no tree and crashes Does any one have an idea how to use bump mapping(or parallax) and optimize a scene by an OctTree?? I would be glad if someone helped...

I 've the same problem: do you use irrlicht9 or 10 ?
Have you all the textures for the mesh ??
It seem that having no textures or only someone make problems.

its because of niko's inflexible vertex types. octree scene node can use S3DVertex or S3DVertex2TCoords, but AFAIK he never put in the code to allow it to use vertices with tangents

so is there no way to do it?