QTR-Quadtone RIP

I am having some difficulty getting to grips with QTR on my Epson 3880 (Mac OSX Mojave). I edit my Raw initially in Lightroom but then go to PS and Silver Efex Pro saving as a ProPhoto RGB 16 bit Tiff. I then print on Photo Rag via Lightroom using Epson's ABW system. The results are quite heavy - lots of absolute black and very bright whites (which I like). But I thought I would try QTR to see if I couldn't keep the dark blacks but get a bit more separation in the midtones.

I have installed the latest QTR successfully and printed on Photo Rag using the supplied neutral curve for PhotoRag. I assume the correct way to do this from Lightroom is to choose "Printer Manages Colour" and then set the relevant curve in the QTR driver. Is that right?

The results were certainly neutral but do not match at all what I see on the screen. Most of the contrast has gone and the darkest areas (which according to LR are absolute black with no detail - and indeed as printed via ABW with no detail) now are rather anaemic and flat. I quite like the midtones which are indeed lighter than their ABW equivalents and could be good if I could just increase the density of the whole picture.

So any advice as to what to experiment with? The only control in the QTR driver that appears to deal with density are under the Advanced Adjustments - Ink Limits and Gamma. Would playing with those help?

Should I convert my Tiff in Photoshop to QTR Grey Lab or to QTR Gray Paper?

I think I may get to like QTR but getting an initial foothold on the slope to learning it is proving a bit confusing, so any advice would be most welcome.

Thanks