secondary router

I am using a DD-WRT VPN second router connected to the XFi router LAN port. It gets a WAN IP ok (172.16.12.106) but it appears to be blocked to incoming traffic.

I cannot figure out how to allow ping (ICMP) and port forwarding to this IP.

I would prefer to keep this configuration (as opposed to bridging) as it allows me to have two LANs, one with a VPN and the other without.