The first step is to ensure that your firewall is not blocking StreamTorrent NE. The steps below are for Windows Firewall, but the principles apply for any firewall software you may have installed.
By default, most programs are blocked by Windows Firewall to help make your computer more secure. To work properly, some programs might require you to allow them to communicate through the firewall.
To allow StreamTorrent NE to communicate through Windows Firewall
Open Windows Firewall by clicking the Start button , and then clicking Control Panel. In the search box, type firewall, and then click Windows Firewall.
In the left pane, click Allow a program or feature through Windows Firewall.
Click Change settings. If you’re prompted for an administrator password or confirmation, type the password or provide confirmation.
Select the check box next to StreamTorrent NE, select the network locations you want to allow communication on, and then click OK.
In my experience this should be sufficient, and no further Port Forwarding should be required