I thought you was supposed to save the render. I know next to nothing about Python so I don't know if you can make it "invent" a filename. But just close it without saving? I don't see why you would want that?

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You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.