Unlike Poser, UVmapper gives nice straightforward error messages.
When it says no facet info, it means that the OBJ has a vertex list
but no facet list.  I'd guess this was lost when you used your
modeller ...  Some modelling apps will let you save only the vertices,
to use as a morph target.  Perhaps you accidentally saved it that way, 
or the modeller decided on its own to save that way.  

If the first import back into Poser looked OK, it could have been because
you had the original OBJ with the same name in a different folder, and 
then you renamed the new one later on?

(When I run into an OBJ that sometimes seems okay and sometimes
not, it's usually because of different versions using the same name
in different folders.)

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