Digital BW, The Print

Dear all:

I've been using the Nikon Coolscan ED 4000 for 18 months only to scan
B&W negatives (Agfa APX 25, TMax 100 and 400) to print them on A4/A3+
papers (using mostly the PiezographyBW plugin with MIS Quad inks).

I use Nikon Scan 3.1.2. (I have tried Vuescan but was not convinced).

My settings: Mono neg, greyscale, 16x resampling, 14 bit output.

I usually play with the gain settings but do not use the Nikon Scan
curves.

After hundreds of scans (with different kind of negatives and
different ways of process), I am still disappointed with:

- the poor histograms I obtain in PS
- the gap in shadow area (from 0 to 25/30, no data at all!) which is 
quite annoying for printing with the PiezographyBW plugin since it 
requests strong blacks...

Is there any tricks I missed?

What are your settings when scanning B&W negatives?

Thank you for your help.

JM Humbert
Paris, France