Huh.  That looks a bit like the Grouping Tool bug which the Pro Pack had when it was first released.  IIRC, Poser was dropping the last listed polygon in a geomCustom group.  How many polys are affected?    If you omit the line feed at the last line of an obj file, Poser will similarly drop the last listed polygon.  Wondering if smoothing is somehow similarly skipping out on it process too soon.

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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.