Hey G T R, I realize this is a pretty old thread but oh well. I had some serious troubles awhile back getting an .x exporter to work properly from Max. After hours and hours of searching I finally found a working exporter that was almost perfect on some obscure indie developer's page.... it's lost somewhere on my harddrive though. I'll let you know if I find it.
But unless you have a serious need to use .x files it seems to me the easiest way to get a file from Max to DBP is to use Konvurd, which can import 3ds files and export dbo files. From Max's native format to DBP's native format sounds pretty clean n' nifty to me, and it works a charm!
Find it here (the link is also in issue 40 of the newsletter) http://forum.thegamecreators.com/?m=forum_view&t=76276&b=5
Neeeeeeeewom!