The last line is your answer. "preview mode" is just that. 
Not a render in any way but just the openGL preview. Do a proper render and I'm sure the problem is solved.

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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.