You may need to configure your firewall or proxy (if you use one) to allow traffic on port 80, 443, and 667. I've also noticed it opens port 7667 but they didnt include that in their
FAQ about firewalls. In any case, if theres anything limiting traffic on these ports, you might be unable to connect.
If you still have trouble, you can try contacting
support, though it seems their standard answer used to be to update your video drivers. Havent heard that one in a while though