Hey RonR,
I'm having exactly the same issue, no ringing for incoming calls. In my case, everything worked for a couple weeks, we had a day long power outage, and when it all came back up, I lost the incoming calls. I re-setup the box using the google voice config tool again, I made sure google is forwarding to google chat, I've tried a couple of different phones, and still no incoming calls make it through. It rings a few times and just goes straight to voice mail. I'm not sure what else I can check, but I'm thoroughly frustrated with it. Any help would be great.