As far as I know, once you've imported a figure from Poser into Blender, you can no longer pose or use morphs. You could still use the textures. I used wavefront OBJ format to export from Poser into Blender.
I don't know if you can. I do my posing in Poser. Usually, I import the Blender items into Poser. But this one I did backwards, Vickie was imported into Blender, no rigging, as a reference for modeling the other stuff.
Have you tried Collada?
DAZ Studio now exports to Collada 1.4, and Blender has a script to import Collada 1.3 and 1.4; people on blenderartists.org claim it used to work, until somebody changed the Python API.