I did the whole thing in Paintshop Pro X.
When any NR software opens an image, it tries to find uniform areas of the photo from which to sample the noise. When I run the NR tool in PSPX, I simply delete all of the automatic sample locations and manually draw my own sample boxes on the blotchy noise I want to remove (in fact, most tools may not even think it's noise because it's so large.) Manually choosing the sample locations is critical. I don't know how to do this in Neat Image. I know Noise Ninja lets you pick sample locations as well.
I attached a picture of the PSPX NR dialog box--you can see in the "before" pane the several sample marqees I've drawn to give the tool examples of what I consider to be noise (NR is the first step, so the image is still yellow and dark.) Since the "after" pane updates every time you draw a new marquee, you get immediate feedback on how the result will look. The larger the selections, the better since it allows the tool the remove lower frequency noise. These few selections were enough to allow it to "get the idea" of what I want removed for the entire image.