Good to hear. Happy sharing, and best wishes with the greyed out firewall setting. Just a belated thought: your wireless card (Airport?) functions as a firewall, IIRC. I wonder if the AirPort Admin in your Utilites folder (or whatever controls the wireless card on your Mac) has taken over controlling the firewall/port forwarding functions, so that is why your Firewall settings are/were greyed out.

Cheers