Thank you, both of you.
@ Believeable3D: the only reason I did the morphs using Morphs++ for V4 first and then exported to Blender3D was to see if the changes in the mesh could be exported to a 3D program. Turns out they could. Morphs++ don't add any geometry to the basic V4.2 object, does it?

So, now I have a mesh shaped differently to the original V4.2 (verts have been moved around) but nothing else is different. I.e., ( BeyondVR ) I'm not doing anything to the mesh except moving the verts around a wee bit more. I'm not adding any, not changing their order. Just taking an already-changed mesh and modifying it a wee bit more.

I could have achieved the same result - theoretically - with the Poser Morphing tool. For the sake of argument, let's say I did and exported the result of that. I don't want Morphs++ to be called with my new morph: I just want one dial where the user would dial in the degree that they want my character's ... um.... characteristics to change V4.2.

So, I want a PMD? Partial Morph Dial? Happy to have a go at that. I'm not going to bore you with a lot of remedial Morph Creation questions: could you point me at something current that I could study in terms of tutorials?

Thanks so much!

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

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