If you can't reach that page for the port test it means that port is blocked for you. This will probably be due to either your modem/router not having UPnP capabilities or isp provider blocking this port or other softw blocking.
Without knowing the answers to the above questions it's difficult to offer specific advice. You could try another port. Go to LW's menu Tools>Options>Advanced>Firewalls & change the listening port from 6346 to another like 3500, 80, 20282, or 443. Press apply after making the change. Then go to File>Disconnect & wait a minute & then File>Connect. Give it at least 15 mins to try to connect. Do this for each of the port no.'s I listed.
If it still doesn't work, then it looks like a modem/router NAT firewall issue & you'll need to do port forwarding (open a port.)
http://portforward.com/routers.htm The steps there are 1st to set up a static ip (very important to do this 1st & do it properly!) Then forward a port such as 6346. Then within LW:
Manual port forward instructions & sample image & 2 posts after that.