I noticed that if I import an OBJ which has all the Vertex groups setup (using import settings: Keep Vert Order, -X90, Poly Groups)  ...and then I add the "Smooth" modifier, it breaks up the mesh at the Vertex Group seams. (as seen in the attachment above)

Is this just how it works, or is there a way to smooth without breaking it apart?

Also, if it is how it works, is there a simple way to repair it?

In the picture, I have repeated the smooth 5 times to make the gaps visible for effect...

The reason I need to smooth it, is that prior to smooth I am shrink-wrapping it, which makes it a little, less smooth...

OK, interesting.  I imported the same OBJ, but did not click poly groups.  (so it had not vertex groups), and when I ran the smooth modifier it broke apart at the same place...intriguing!  Obviously its not related to the vertex groups, but maybe I did something in the process of creating the vertex groups to the mesh...?

Quote - OK, interesting.  I imported the same OBJ, but did not click poly groups.  (so it had not vertex groups), and when I ran the smooth modifier it broke apart at the same place...intriguing!  Obviously its not related to the vertex groups, but maybe I did something in the process of creating the vertex groups to the mesh...?

You need to weld the groups when exporting from Poser, otherwise each body part group is a seperate (piece of) mesh (as you've discovered).

OK, I figured it out...

I did a AKEY in Edit Mode to get all of the vertices, and then a WKEY (remove doubles) and I had about 5000 of em...  LOL!

nruddock thanks for the reply!  Not sure if what I did accomplishes the same thing or not?  If not, I'll give it a try!

I did read that exporting from poser makes some small mods that you don't get if you just grab the OBJ direct, so I typically avoid the export operation.  I think it was in some ZBrush related forum posts.

Quote - nruddock thanks for the reply!  Not sure if what I did accomplishes the same thing or not?  If not, I'll give it a try!

It's not, welding is a seperate option.
If you don't weld, the polygons all belong to one group, but it's still in several bits.

Quote - I did read that exporting from poser makes some small mods that you don't get if you just grab the OBJ direct, so I typically avoid the export operation.  I think it was in some ZBrush related forum posts.

That's correct, unless you choose the "As morph target" option when exporting, any translation, rotations, and scaling applied by the CR2 are incorporated in the exported OBJ (which you you may or may not want), and the groups are split (Poser does this when loading and welds internally).

As the DAZ figure meshes are properly welded in the OBJ, you can avoid the trip through Poser by removing the groups using UVMapper.
(basic recipe here -> http://poserpros.daz3d.com/forums/viewtopic.php?p=370035#370035)

I just imported V4 from the geometries folder with polygroups selected, ran the smooth modifier up to 30 and used the sculpt brush across several group boundaries without any separation. See the attached image.

So follow nruddocks advice.