I found a site to download NWC files. Some of them have two lines, and some have three. I think it's called "arranged" if it has two lines. How do you "arrange" an NWC file and cram it into two lines if they have the same clef (treble/bass)? I know it's possible; I've seen it done before. I'd just like to know how. Thanks in advance.
You need to set the staff properties to "layer with next staff." To do that, go to the top staff, then press F2.
After you've done that, the View menu option at the top of the screen has a setting to "allow layering."