Windoze 7 may not like the post box...............
Hmmm... it's a little different, but I don't see any reason why you couldn't.How are you venting the plumbing in the basement? Could you just tie into that pipe?
Sounds like you'll be running 2 into 1...correct? I see no reason it wouldn't work but you'll probably get some "backflow" when one fan is being used and the other is not.