I think even before getting into that tunnel configuration I'd be curious about whether or not those RIP packets are making it to your endpoint after making the changes suggested by Marius; try this command:
tcpdump -i any -vvv host amprgw.ucsd.edu
If your firewall/routers are configured correctly, you should see those packets even before you start configuring your tunnel.
I also took a look in the portal & noticed that your gateway doesn't appear to have any subnets associated with it. I'm not sure if that impacts whether or not the gateway will send RIP packets to the public IP of your gateway, but it'll definitely put a crimp in your connectivity once you get ripd running.
Best, -Steve kc8qba