I took the head of V4 into sculptris and increased the mesh *4, saved the base head then did the morphs as targets for the base. On loading the base into poser and loading the MT, when using the morph dial the head shoots off 1000 mles in some direction. On zeroing all translations the MT had taken, but how do I keep the head still - and why does it do this. Any ideas please

Just as an experiment, load V4 into Poser, then import the obj. you've been using as the head morph with all of the import option boxes unchecked. How does V4's head compare with the import?

It's usually one of two things: the vertex order is somehow being changed on export/import, or the scale is not exported/imported with enough precision.  In your case it sounds like scale problem.  The usual workaround is to export from Poser (or better, don't export at all, work with a copy of the base OBJ) -> scale it up 1000 times -> import to sculpting app -> "do stuff" -> export from sculpting app -> scale down 1000 times -> import to Poser.

Quote - Just as an experiment, load V4 into Poser, then import the obj. you've been using as the head morph with all of the import option boxes unchecked. How does V4's head compare with the import?

well, that made a heck of a difference. With all options unticked the head was the right size and in the right place

Sadly pjz, sculprtis is still WIP I think and offers no option for rescaling :(

There is a freebie utility called Scaler3c. I think it might still be at Renderosity. Search for it here, or on Google. It will do the rescaling for you.

It's strange that the head morph obj appears to be the same upon import. Usually when the head morph makes the head fly away there is a difference in its size or location. I don't use sculprtris, but other Poser users have had success with it.

Yeah the rescaling middle-step is a common thing, look at that scaler utility Paloth mentions.

I'll get that scaler, thanks pjz, Paloth :)

I have no problems with making morphs in sculptris.
You should not deny it to scale (it will automatically unscale on export), but you should not move the mesh or scale it within sculptris. It worked perfectly for me so far.
And there is no need for a scaler.