Hi Fingerprint,
Without having the model number of your Modem, I cant tell you exactly the link you need to have to manually forward ports. That said, most speedstreams have the ability to use uPnP forwarding. The new
WinMX Community Patch can forward for you but you will need to access your Modem configuration pages and 'Enable' full internet gateway decivce.
Once this is done and saved, Go to WinMX > Settings > Incoming TCP set this to Listen on (radial tick) and it will set port 6699.
Then go to In/Out UDP > Tick Send and receive on port 6257.
Close the Settings Page and Restart WinMX.
If you have porblems beyond this Fingerprint post back here we'll help you get it sorted.