Hi @musicullum !
It looks working 
Thank you very much!!
First we had a round or two (doing, saving, closing, opening, checking) until I found out:
“Ctrl+Click +HOLD & Select < nc >” is the right way to do the job (first clicked as we do for “set it Not-Set”, but it selected the one where my mouse-pointer was). We’re good now with ports NC’s 
It’s weird then to make this happen when simply selecting < nc > I guess, because of the things you mentioned before, do I understand right?
p.s.:
At one combination only I found the app fails so far: if NC-ing the very first port (in any type of). Then it always filled up with a reachable port at opening.