Both your modem & router have internal firewalls. So now wonder. You should forward a port for both.
1. Instructions for port forwarding for you modem see:
http://www.portforward.com/efficient/5200.htm for instructions on both setting up a static ip & forwarding a port;
Port 6346
You must set up a static ip 1st. On the link I gave you'll see a link to static ip for Speedstream. At the bottom of the following page you'll see another link for setting up static ip. You need to follow thru both of those instructions for setting up the static ip. Then do the port forwarding.
2. Your router also needs it. See
http://www.portforward.com/smc/7004v...forwarding.htm
3. If you're using a lesser version than 4.4 then you will need to force ip within LW:
Force IP instructions & sample image If you are using LW 4.4 tell us.
Get back to us about how things go.