None of this is working.
Changing the firewall settings you mentioned shouldn't matter, since these requests aren't coming through the router to a client on the LAN. It's the router itself hosting the service, so the firewall shouldn't interfere IMHO. If it does, that seems broken. Can you issue a firmware fix for this ASAP? The system log on the router isn't even reporting any refused connections when I try to connect to my router remotely, this also seems broken & suspicious.