This is a common problem.  When you made the morph, the OBJ file
wasn't located exactly as it was in Poser. 

The way to avoid this: 
Bring the original (unmorphed) OBJ into Poser.  Scale it and locate it so it
will be correct for Poser's use.  (That is, make it the right size for a human
to hold, and position it in a way that will be practical for easy holding.)

Export the OBJ from Poser.  Check the 'preserve original groups' box
but not any of the others.

Then use this exported OBJ to make your morphs.

When you bring this OBJ back into Poser, be sure all the boxes
on the OBJ import panel are UNchecked.  Don't move it or scale
it again until you've applied the morphs.
until

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