Ta, Andrew. Yes, it is the ViewNX 2 version.
I thought that was the case with this program - as you describe - unpacking the raw file.
I have heard pros and cons about what the others might do, like RawTherapee and Fast..., ie, whether they only open an "embedded jpeg" (whatever that means) and let you "work" on that.
Certainly, I cannot save an opened NEF as a 16-bit tiff using FastStone, but it does allow saves as a DNG (16-bit, I suppose).
Am.