Tiny Firewall and NAT

Does anyone familiar with Tiny Personnal Firewall know how to configure it to allow network address translation through the machine running it?

I use Win2k advanced server on my home network, and it runs NAT to connect the other computers to the internet. When I turn on the tiny firewall, packets go out to their destination, but are not forwarded back to the originating machine. Even when it is set to "Don't bother me", where all traffic is allowed if it is not explicitely denied, it does not get through. For testing purposes I removed all of the denial rules, so technically the firewall shouldn't be doing anything. However I have to stop the firewall entirely before traffic is permitted.

I may just have to go with something more configurable. If it's possible, any insight is welcome.