the real problem are skins since when you convert them to gmax you loss all the data and you have to reapply it. It dosent matter if you use 1 or 2 skins for if you use several (like I do) it becomes really a pain...
There is an importer the exporter would be do the same steps but backwards (I dont know script programing or w3d arquitechture) but it logic tell me this