The way PSP handles camera raw leaves a lot to be desired. What Psp does is convert (at Default setting) then expects you to make the changes on the converted image. The benefit of Camera raw is that The output from the raw can be controlled (exposure colour etc Prior to the conversion.
I would Use you Nikon software to do the process then use PSP for further Enhancement and Noise removal as For the later the tool although dating back to PSP 9 and JASC days Is still one of the best available and the Chromatic aberration remover Is Up there with it For a PDF on the digital Noise removal Written by its Creator www.trevorbowden.co.uk\DCNR.pdf