You could also try connecting through different ports to see if they have blocked ports. Also check your online internet account to see if there is an option to open ports, some accounts have option to do this, depending on ISP, etc.

Ports to try: any between 49152 - 65535. And you could also try ports 80, 427, 443

To change ports using LW 5, menu bar, Tools -> Options -> Advanced -> SuperReallyAdvanced -> Firewalls.
Sample image here: Manual port forward instructions & sample image

However if the ISP is blocking, they might be using a special program that detects p2p software & is able to block it that way.