You can still export a Finale 26 file as a Finale 2012 file, which should help. IIRC one would only be able to open a 22-stave file as read-only.

You could also try exporting as XML, and importing into 2014. But I think the staff limit still holds.

But wait! Does the staff limit mean per song, or per system (i.e., full orchestral scores?) When I used PM, I did many a barbershop chart (two staves) that went beyond that in terms of total staves. I’d suggest you simply try it, and see what happens.

Well, I got hold of a copy of PrintMusic and did some testing.  Turns out that yes, it will open our files created in Finale 26, but it will not recognize any of the linked parts.  So, you just get a score, and you would have to "extract parts" (like the old days) and format any parts you need from scratch..  Not a very good solution.  I'm ruling out PrintMusic as being helpful in this regard. :-)

Even Notepad would open Finale scores as Read Only back in the day but, yes, exporting as 2012 should be readable in PM 2014. Of course, there's a lot you can't do with it as you've discovered and it's no longer offered for the Mac—doesn't work in the last few versions of the MacOS.

If you're not in a hurry, keep your eyes peeled for possible Black Friday sales on Finale. They've offered them in the past.

Mike, actually PM 2014.5 will open Finale 26 MUSX files directly.  But sadly it will not allow for printing or editing of linked parts that are present in the Finale score.