I have been using ultravnc for a long time now and have never had issues setting up port forwarding for any of my routers. (Linksys, Netgear, DLink). I just switched from TW to Fios and they installed a Westell 9100 EM router. I setup the Port Forwarding but it still won't pass the connection through. If I put the computer on the DMZ it works. This tells me I have the right wan port and the computer is accepting the connections, I just don't have something configured properly.
Below is a copy of the port forwarding.
Local Host Local Address Network Address Public IP Address Protocols
localhost 127.0.0.1 Any Any TCP Any -> 4567
192.168.1.100 192.168.1.100 Verizon FIOS Service Any 0000007231485188 - UDP Any -> 63146
"Computername" "ComputerName" Any Any VNC - TCP 5800 -> 5800
TCP 5900 -> 5900
UDP 5800 -> 5800
UDP 5900 -> 5900 Active