its about 209000 polygons~~~i have to use XSI?
I think someone made a script to go from .3ds to .mesh, but the model converter the Devs used converts .xsi to .mesh. Generally people do the main model in 3DS Max, save it to a intermidate file type like .obj, import it into the XSI mod tool for the finishing touches of setting the mesh points, hooking up textures, and tangents, then save to .xsi so the converter can convert it to .mesh.
If you directly tried to convert a .3DS file, I'm shocked it didn't immediately crash on you...