Sorry for the lateness. Anyway I had the same problem usually it don't always import 3ds files (something to do with the mesh on their files) Instead I use the 3ds Max 5 program to import 3ds or make my own files from scratch. I know this is hard to explane but you need two files. The utility and the plugin files. Go to
http://www.wounded-heart.com/downloads.asp
That's if you have 3ds Max. I know Barnes & Noble bookstores carry 3d mags and with all kinds of demos they have. Bottom line, I hope one day other programs will incorperate SM files as well and not just for NL.