Even though I picked a material in DS, all I got with the obj was the black sheen. So I go to the Material Room. Thankfully, the duster has only one material zone, Robe. I start with a transparency map. Click browse, I go to the Textures folder in my DAZ 3D Library, find Rhiannon/Waterfall, and add the 01 trans map. I then add the 01 bump map and the 01 specular texture. Now even the iray materials look OK. I use MAT Writer 2014 to save as a material setting for the garment.

Repeat that process for all the options.

Here is Cynthia La Femme wearing the Waterfall Duster.