Okay.  Here's an initial idea for an automatic chain-building feature.

Once the first link is generated, there's no reason to calculate a new geometry for the subsequent links.  That fist link can just be repeated, with appropriate rotation and translation of the geometry.  My thought is to add a "Make chain" dial.  At zero, it would do nothing.  If non-zero, it would determine the long axis of the first link and move additional links in that direction, rotated cross-wise to the plane and translated by the length of the link minus twice the Thickness.

The "Make chain" dial would determine whether the links are added in a positive or negative direction, as well as how many links will be added.  So a setting of 10.0 would create ten links along the positive side of the link length axis, and -10.0 along the negative.

The only trouble (aside from working out all of the matrix handling and interpreting positive or negative directions if the length axis is not aligned on X, Y, or Z) would be a case where the first link is perfectly round, with no longer axis.  In that case, a default would need to be applied, and I'm wondering whether X or Z would be preferable.

There are probably complications which don't occur to me offhand, but the above seems feasible.  :unsure:  I'll tinker with the idea and see what happens.

===========================sigline======================================================

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.