This is good.  Thank you. 

I have a couple of questions.

"the intersection/bounds checking code doesn't really distinguish the direction of  the ray being cast" - Are you suggesting that it needs to?  Or is this a moot point once the region code is repaired?

"if you're not using the  center version, then the direction vector ('ang') needed is just the vertex normal" - So the normal vector itself serves in place of the line?  Nothing needs to replace the removed calculations?  (I've never been able to puzzle out how a vector can be equivalent to a point in some regards, yet possess direction or magnitude....  Cage is a bit slow.)

You did quite a bit.  Golly.  Thank you.  I'll try to measure up to your additions.  (Try to, yes....)  :)

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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.