I have removed the cameras and then I was able to import it in max9: http://maxwell.griffinlair.com/max89.png
I assigned a MaxwellMaterial on the layer and rendered the scene without a problem.
Could you remove the cameras and let me know if it works for you?
I've noticed you have two Xrefs loaded in the scene. Try first to open those xrefs and save them with max 9 after checking all the materials and cameras are ok. Probably they are not giving problems to us as we cannot load them but you can.