Hey. The router is set up to automatically open the necessary port with UPnP, so when Deluge is started and wants to open a port, it should be allowed, but for some reason it’s not going. I have not had any problems before with it with my other Linux and Windows experiences.
The only thing I can say is I never use UPnP. I always add all the ports manually. And I would say check and check again!!!
You have to add ports to your firewall via Yast - Firewall - Allowed services - then the Advanced tab. Add ports here.
Hence I would say setup ports manually in your router, select specific ports for tcp, udp - say