I've uploaded three different JP insertion poses which I've been using, to the Developer's Site, as neck_JP_injections.zip.  I should have an additional pose later today, but I'll have to do some processing first.

The first of these poses is ripped directly from the Batgirl character I uploaded and seems to work tolerably well with Antonia 124.  The others are my efforts to work with version 125, before I realized that the changes were (perhaps inevitably) going to be in conflict with the new JCMs.  The one I'll have later is just a more recent effort for 125, which has the same problems with making the head bend look worse, due to the JCM incompatibility.

I really suspect that this is an area where we're struggling with the inherent problems of Poser's joint system.  Poser's scaling is even more rubbish than its joints.  :lol:  I doubt any workaround we can some up with, on a user level, can compensate for the bad joint system in all cases.  Possibly SCMs (Scale-Controlled Morphs) in addition to JCMs could help.  But there will be the problem with the morphs being linear and the joints not being linear.  (I keep saying it: the true solution to Poser joints is still actual vertex-mapping with transferable skeletons.  This would enable greater subtlety and more user-control in the joints themselves, before any fixes are applied, and would ultimately be easier to set up.  Think of how much easier conforming clothes could be!  Sigh.)

===========================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.