Did Blender export a .mtl file with your .obj?  If not, Poser won't look for any textures upon import.  Are the textures you're using in Blender packed?  If they are, they'll need to be unpacked for Poser to find them.  (Umm.  I should probably ask, too, if you'd exported from Blender using .obj....)

I recently exported a .obj from Blender and had to unpack all of the textures, then place them with the .obj and .mtl in the same folder.  Then Poser imported everything correctly.

You will lose any texturing which is applied on the shader level when doing I/O between Blender and Poser, unfortunately.  Only a texture map and the diffuse, specular, ambient, (and possibly transparency?) settings will be passed by the .mtl.

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.