Normals_forward is't a button but a checkbox :o) You can see it on your material room screenshot, it's the last box, right above the prewiev of the texture (in the PoserSurface) list.

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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.