@JoEtzold ; First let me thank you for pointing out that you are NOT using Poser 12 to support your argument that what we see in Poser 12 is not happening. That makes a whole lot of sense.

Now, I really did think I was going to need to spend this much time for I thought I had given enough information and samples BUT here it goes:

The scene is the SAME, very simple. Only thing I change is the RESOLUTION SIZE in Poser then without changing anything I open the render in Photoshop and take a look at the Document Size.

Now here is what Goes Into Poser 12 and what comes Out (forget about the "Resampling" for I am changing NOTHING)
***Note: Two Renders, Two different RESOLUTIONS asked for but BOTH come out as 72

Now here is Poser 11: Same scene, ONLY changing the RESOLUTION, I change Nothing when I open it in Photoshop.
***NOTE: Poser 11 gives me One 72 Resolution Image and One 300 Resolution image

As the Pixel Dimension are NOT changing, what this tells me is that Poser 12 is rendering at a MAX Resolution of 72 pixels/inch but Poser 11 is rendering the requested 300 pixels/inch ALL with the 640x480 .......or is Poser 11 lying and really only rending both at 72?

So; is ANY version of Poser actually Rendering at resolutions higher then 72 ?? Poser 11 claims that it is, but Poser 12 is saying it can't.

So I will just leave it at this final 'explanation' from the web: