Blocking WMC In Firewall?

This is a follow up to a previous thread that MG helped me resolve. I was able to block update notices for PowerDVDCinema11.exe by simply finding the rule in Windows 7 Firewall and disabling it.

However, here's the issue.

PowerDVD also runs inside Windows Media Center as an "Extra." I use it to play Blu-Rays. When loading PowerDVD from my Start Menu as a stand-alone app, everything is blocked fine (via Windows Firewall). However, when running it as an "Extra" from within Windows Media Center, I get the update notice again.

:banghead

So, how can I locate and block the necessary files for Windows Media Center in Windows Firewall to prevent this small hole that PowerDVD is finding it's way out of through WMC and connecting again?