Yes Alt+Print screen takes the active window. I have a feeling that ctrl-print screen also should do something special but I don't remember what and I can't see any difference between that and a regular print screen :o)

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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.