It came to my attention today that some firewalls block websocket traffic on port 80. For this reason, I have split out the webserver and socket.io traffic to 2 different ports.
In config.js, IO_PORT is the socket.io port. This should NOT be port 80. WEBSERVER_PORT is the port that the built in webserver will bind to (can be port 80, but this requires root permissions).
You will connect to yourhostname:WEBSERVER_PORT, and use yourhostname:IO_PORT as IO_URL.