At the bottom left of the Finale screen is the page number and a left and a right arrow. Click the right arrow to go to page 2. If that doesn't work, there is no page 2 - you must enter more music to add additional measures and then additional pages.

You're a tuba player, eh?

Yep.  Makin' mischief in the back row....

I am working from an eighteen page score that I moved from my PC to my Mac.  The playback plays the entire score, I cannot use those arrows to get the page to advance.  Part of my problem is that I have Finale on the PC, and Print Music on the Mac.  Using Finale, I was editing the score, and lost about 3 hours of work when the program "couldn't find" what I had been working on and reverted to the previous form.  I decided to try working on the Mac, and I can't move either the score or any of the parts beyond page one.  

Go to the Utilities Menu and choose Update Layout (or just type Command/U). Do the pages advance now?

That did it! Thanks for the help!!!

Since Finale allows 2 installations, why PrintMusic on the Mac?

Because the Finale is the one they offered as an upgrade for $99 last year; I would have had to buy one for each program on that deal.  When I upgrade that Finale, I'll double up onto the Mac.  

??? You are still allowed 2 installations. One can be a Mac and the other a PC.