What are the proper settings for KTorrent behind a firewall?

I have the recommended port 6881 TCP/UDP redirected from my router and confirm it is open with whatsmyip.org, but I am not seeing much upload traffic and Dimeadozen says I have a possible protocol error or router misconfig. In the Settings-KTorrent I see a recommendation to also forward port 8881 for UDP, but when I do that, the test says there is no listener!

Is there some magic step that I’m not doing?