Last note,

Which most are probably aware but just in case. Unless you're utilizing a dedicated exporter like GoZ or PML or similar, always work from the figure mesh in geometries rather than a figure export live from Poser. Single actor morph targets are fine from Poser but attempts at FBM from Poser scene will result in an unwelded mesh that's unworkable because of body part group splits. Poser unimesh is leading up to correcting this but as yet hasn't reached that degree of implementation.

Generally wrong vertex order problems result from welding or splitting the mesh, and sometimes translation errors. Wings3D is notorious for wrong number of vertices or vertex order problems, and seems to have gotten even worse in latest versions, it also does weird things with groups and will split a mesh into body part groups (often in unusual ways) even with static grouped imports from geometries. With Wings I found it best to morph on an ungrouped figure mesh and project the result as I mentioned earlier. Blender is a lot more forgiving. The 2 things that are most critical are do not split mesh and maintain vertex order, with polygroups being a strong third. I use PML to circumvent most of these issues but those first 2 are important regardless. PML could'nt care less about polygroups so I don't worry about it.