@midinick - I use both Poser and Daz Studio. My 3D program of choice is Daz Studio because I like it better, it offers more things/effects for me. I use Poser only if there is a poser products that has special effects/materials that I want. When I use that Poser product I save the rendered file to png same as Daz Studio. Once I have rendered all of those Poser items they are saved in a folder. If I want to combine the rendered items from Daz and Poser, I use a 2D program. My program of choice is Photoshop. Each of my rendered pngs that I plan to use (remember each png has a different type effect which was created in my 3D programs) is imported as a layer into my 2D program. I apply the layer effects that I want on each layer to get my composite.

Things I never do

1. I never create a file in Daz Studio with plugin effects, scripts, shaders, special effects then export that file to  a non-Daz studio format. Meaning obj, fbx, etc because when these things are exported, they lose the intended effect. Some things are specific to Daz Studio. Instead I export the rendered image with the effects to png to use in my 2D program. 

2. I never create a file in Poser with the poser materials or scripts applied then export the file to use in Daz Studio. Some things are specific to Poser.

Things I do

1. Create the file with its special effects in that specific program and render it, then save it to png. 

2. Use the rendered image (png) file to create my composite in my 2D program. Each file on a separate layer and I apply brushes, overlays, styles, run actions if wanted. Once I get the result I export my file to jpg.