From what I have read that NetComm router should have a firewall. Can you find it in Set Up?
If you can find the router firewall, turn it off and see if Avast starts logging inbound and outbound traffic.
When I first started using Avast 8 the firewall logs were empty. I didn't look at statistics, so I don't know what that showed. I tried to turn the router firewall off, but It wouldn't let me. I had to call AT&T and have them disable it remotely. Then Avast started showing the firewall traffic.
When I turned the router firewall back on, both Avast and the router show the firewall traffic.