You only need ambient for this. Diffuse hasn't been required for previews since Poser 8. Just attach the image to ambient_color and set diffuse_value to 0.The simplest way would be to use EZDome 3 like Miss B said above, but if you need a quick and dirty HDRI in Poser, all you need is a sphere with the normals facing the inside of it, and of course, it has to be UV mapped. I believe Poser Pro 11 already ships with a few props for that purpose, like a sphere and a dome. They are in the Props library, but you can make your own if you like. Once they are in your scene, just map a texture into it, plugging it into the "Diffuse" and "Ambient" channels. The prior is to make the HDRI image to show in Poser, and the latter is to make it emit light. The intensity is controlled by the ambient "value", where 100% is "1.0". Any values above that will saturate the Diffuse image, turning it into white. This is why EZDome uses 2 spheres - one just for the diffuse, and one for the ambient (emission), so we can increase HDRI intensity independently from the diffuse backdrop.
Hope it helps.
I just asked him how long the links will be available. I already have most of them, but I need to know where to link to in my Directory.OK, just got a link where you can download EZDome, and some other scripts if you want to try them. You can find them here --> Snarlygribbly's Poser Scripts
Don't forget, as I mentioned in my post above, in order to use the EZDome script, you'll also need Bagginsbill's EnvSphere, which you can find here --> BB's Environment Sphere
I'm slowly making my way through the list and noticed that No Emotion Hdrs has a CC NoDerivatives license, which would exclude any public use of the images for CG works.
If you read the very next line:
NoEmotionHDRs by Peter Sanitra is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License. Based on a work at http://noemotionhdrs.net. Permissions beyond the scope of this license may be available at http://noemotionhdrs.net
And the page it links to states:
NoDerivatives — If you remix, transform, or build upon the material, you may not distribute the modified material.
That basically means that you can only use it publicly as is. Using it in any other from, including in a render, would be a derivative.