Just proved it is not just my pz3's that are maybe faulty... 

Loaded pz3's supplied with 2 Rendo products... recently released and the same thing happens.

pz3's load with ultra bright lights.... you can move the scene around, but as soon as you try to alter the light intensity... pooof... P7 vanishes... no error messages... P7 just shuts down.

"You don't have to be mad to use Poser... but it helps"