The material type is the button next to the drop down menu. It says multi/sub-object. I should have said multi/sub-object when I said composite in my last post.
The type of the materials in the list are what matter. Looks like they are of type VRayMtl, which only works with Max's off-line renderer. They will not export to OSG format. I think this model was not created with real-time exporting/rendering in mind. The density of the chair mesh in your last screen shot also suggests this model was only intended for off-line rendering.
Don't know if you need this kitchen scene, but I've exported this free kitchen model from TurboSquid successfully:
http://www.turbosquid.com/3d-models/...kitchen/363010