Associate
Firewall/NAT>Port Forwarding
1.Tick Show Advanced Options
2. Select the interface that is your WAN port
3. Tick "Hairpin NAT" (allows you to access the forwarded port from another computer behind the same router using your public IP as well as your internal IP) Tick Enable auto firewall.
4. Select your LAN interface if you want the port forwarding on a single interface or select "Switch0" for the port to be forwarded on all the ports that are part of the switch.
5. Add Rule Original Port and Forward to port the same, Protocol is probably TCP, add the IP of the NAS
6. Repeat 5 for the other port.
Cheers DIABLO, that's what I tried yet the NAS still reported it as not functioning for UPnP, yet on turning off my wifi on the phone and logging in via mobile phone signal I can see my NAS freely, so I'm going with the NAS is somehow wrongly reporting the fact it's no visible.
Will see if it all still works when it next gets rebooted.