www.turbosquid.com/gmax - This site gives you a serial number so you can license the product. I guess they took ownership of gmax when Autodesk stopped supporting it.
And yes, Blender's interface is quite ugly for my taste. The guy who said it didn't work well with the older engines, he was an anonymous poster over at collective.valve-erc.com, a site which Valve took down. So I guess he can't be slapped in the face or experience tcp-ip violence.