That is curious.    The XYZ influence looks correct for a Y-oriented joint order, and the Y orientation looks more correct for X.  Is the influence displayed above weight-mapping or Poser's default zone-based joint influence?

I've always avoided the Setup Room, unfortunately.  This may be a question for someone with Setup Room knowledge.  I know we have a few around here....

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.