If you're dead set on not using Poser import, try using the Rhino OBJ export python script for Poser. (available as a download from E-Frontier) 

The script exports your entire Poser scene as a "Rhino Enhanced" OBJ file along with textures. Rhino OBJ's can be read like regular OBJ's, but they also support things like transparency mapping. 

If I do it that way, I usually load the file into Deep Exploration first, and convert it to a 3DS file. Since the exporter copies all the texture files into the same folder as the OBJ, I usually take the opportunity to reduce any outrageously large image files, as well.

I'd rather stay in my lane than lay in my stain!