Your router has both SPI & NAT firewalls. It also supports UPnP. What I'd suggest is making sure UPnP is enabled within the router, then tick it within LW (tools > options > advanced > firewall config. Tick 'use UPnP' & apply). See if that fixes things. Give LW a good 1/2 hour to settle down, see if it's connected after that time.

If that doesn't help, you can port forward.
Step 1. Set up a static IP address. Do not skip this part!
http://www.portforward.com/networking/staticip.htm

Step 2. Port forward
http://www.portforward.com/english/r...4/Limewire.htm

Step 3. Select manual p/f within LW. Tools > options > advanced > firewall config. Tick 'manual port forward'. Put in the number of your listening port. Apply.