@MikeJ,

From the image I posted, it looks like the neck is welding, but that some of the verts are welding to the right place, and some are welding to the wrong place. I'm suspecting that when Poser originally loaded the 'figureResFile', that it created a list of which neck vertices weld to which head and chest vertices. When the hybrid neck is loaded, obviously the vertices are ordered differently in that mesh, and I suspect that to be the cause of the problem. Perhaps I can find a way to make Poser refresh this list, or perhaps odf has some trick up his sleeve to reorder the vertices.