Dunno if this will help, but in my own case, using a Sky router, the port-forwarding is a three step process.
- First you must determine your machine's IP address and, if necessary, reserve it, so that it remains static.
- Next you need to add Soulseek to the list of Services allowed access through the Firewall.
- Finally,
you must create Firewall rules to allow traffic to and from that
address through the Firewall to the IP address of your machine.
In my case, it was the second step I had missed which showed the port as closed. Once I set the rule, the port showed as open.
I found all the help I needed on Youtube, and I imagine you can too.
I hope this helps.