I believe the ZPR system has a 12v output that is only ON when any zone is active. You could tie this 12v output to another Xantech box (don't recall the number), that would spit out IR codes when it no longer senses the 12v output of the ZPR68.
I'm sure if you called Xantech and talked to one of the Tech Help guys they could come up with several options for you.
This would probably be the most cost effective way of doing things. ($150 or so in parts, in addition to what you already have.)
You could also have the 12v out of the ZPR trigger some sort of power strip... Might have to beef up the output of the ZPR though. It is ONLY 50ma or so, and most triggers will take more than that to hold them on.
A Crestron or AMX system would be awesome, but those are typically programming intensive, and may well be overkill for your situation.
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