ZEN 7. How do I configure an app to run upon an event, such as Logout?

We are going to push out an MS Patch, and would like to push it out based upon the event of the user logging out. Since the patch requires a reboot, this seems like a logical time to push it.

I don't see how this is possible in ZFD 7. Am I missing something, or can I create a Policy do it?

I'm up for any ideas that will help.