Okay.  I managed to track down some errors in the hair group and hair prop creation and handling code.  The old version was easily confused because I was going about it the wrong way.  This update has been tested to work in all of the basic cases which can exist:

• Neither hair group nor hair prop exist
• Both hair group and hair prop already exist
• Hair group exists but hair prop has been deleted from scene
• Hair prop exists but hair group has been deleted using the Grouping Tool

It's also running a check, before creating a re-named group, to verify that no hair group which is identical to a selected geometry group already exists on the prop.  In that case it declines to handle the geometry group and refers the user to the name of the matching hair group.

One thing it can't do is delete a geometry group once it's been made redundant by being copied over to a hair group (which happens in the case of renaming to avoid duplicate actor names in the scene).  That will need to be done manually, using the Grouping Tool.

The error in restore_roots(), reported above, was possibly (hopefully) being caused by a hair group/hair prop mixup, in which a hair prop with empty geometry had been created.  If so, this update should fix the problem.  If the error persists, I still have some revision to do.  :unsure:

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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.