Whoops. Tabs confused and replied to the wrong thread
I find with some B&W there is benefit but I save jpg’s at 95%. 
Being ancient I used to regularly print 20x16 in B&W from 35mm and find digital has problems matching what I know that can do. 
When I hear mention of grain I get the impression people must have strange memories or maybe had everything done via the local chemists. Actually I feel that there are reason why film etc could do a better job that a pc screen.
Anyway, still no joy with the other version. Looking around on the web it looks like it may be down to scripting changes - NORMAL and others no longer defined. One suggestion was to replace all such with 0 but yet more errors.
So currently just hope some one can sort it out. Not so sure about the version in GMIC maybe because of the sliders and not knowing how these relate to the original version. It looks to be based on channel mixing but I’m only guessing.
John