Hmmm this is weird. I'm using Windows XP so i really cant say if its a Vista problem but usually the only time i have an issue out of Xchange is when i try and use a memory card that is more then 64mbs. I got that error when i tried to use my 256mb memory card but once i put in my brothers 64mb card it worked fine.
The only way to keep your existing Game Saves and add the draft class is with my Xport and Xplorer solution.
Somethings to try with Xport:
Run in Administrator
When it comes up "Please Select A Device" take out the Memory Card and then put it back in and see if it recognizes it
Also there could be an issue with your card or your reader because if Xchange backup is grayed out and Xport will not find the card then that could mean theres something wrong. It could also be a simple driver issue.