We have a similar problem with World of Warcraft and the AS revision. Blocking the ports works on our router but still allows traffic from established sessions even if the port and ip address is shown as blocked. We have a crude solution of a time-switch on the router which shuts router for 5 mins and when it comes back up the necessary ports are blocked. Only downside is teenage son stomping around the house banging doorswhen he is kicked off WoW. The message of no University makes allowances for poor grades if you are level 80 in Wow falls on deaf ears.