I guess I missed this thread because I've been really looking for bluetooth NAP, but glad I found it today.
For clarification, do the kernel/modules/iptables binary in the mobilehotspot project provide working NAT? And you're just waiting on UI stuff?
If so, they'll save me a ton of time getting NAP up and I'd be happy to put together a semi-user-friendly shell script or something for use with wifi. I'm not capable of anything pretty and gui, but at least it might help people unfamiliar with the shell.