After 3 hours of study and trial code changes, a little progress has been made, on the residual basic chain single link, and its 90 degree rotation, In MoI V5 beta.
MoI4 does not have this residual problem.

The ChainMaker script is a morass of multiple names for various ChainLinks.
Note that the Twisted chain checkbox does not have any problem with residual links, nor MoI4.

Most of this post deleted.

Time for a break...

- Brian