After working many years with Finale 2012 I had to upgrade my computer and so the version of Finale needs to be a new version too.
I downloaded the trial version and after realizing the many uncorrected bugs and problems where I already have my workarounds, I discovered that my printout, with the same laser printer I had never problems with, has no solid black, it prints a kind of like grid, with many white dots.
I tried many hours, days, all kinds of solutions, I had a long conversation with the Make Music help guys, of course I tried everything they suggested starting with firmware update to the smallest print dialogue change; nothing helped. Also, the pdf version takes this behave with, only if I export with graphics tool it is a bit better, well, maybe just a bit more blurry.
No other docs have this problem, and I tried also with another computer with different OS, the same thing and that makes me believe that this must be a Finale problem.
iMac newest, OS 10.14.2 Samsung laser printer, Finale v26