Proper Netfilter (filter/masq) options with MAP-T

Greetings, all. I'm working on a MAP-T deployment with snapshot on raspberry Pi 4 (r13850-e363470d1a). I'm able to get the DMR and BMR configured correctly via DHCP (verified with pcap and also with the map module on WRT generating the interface correctly with proper settings (ubus call network.interface dump).

The problem now is that nothing seems to be getting translated. I had configured a GA release on x86 VM and setup the MAP interface statically and it worked fine.

I suspect it has something to do with the netfilter settings either not passing the packets to the correct chain, etc.

What's the base firewall settings I need to allow "lan" dual-stack and "wan" single-stack ipv6 with MAP-T. As it stands now, clients in the PD range can browse with v6 all day long but their v4 traffic dies at OpenWRT.