The horizontal movement bar (that lets you choose page number or bar number) at the bottom of the screen is no longer there. Navigation in a larger file is pretty tedious with the hand grabber.

What are your program settings in Preferences - New > New Document Windows ?

View 100%

Page View: Book style row

Maximize

Show number bar

Try changing the settings, and see whether that helps (as a test, not as a solution).

Try e. g.

Page View: Looseleaf Style: Current Page Only

Tried that, no change. The horizontal bar disappeared in the middle of a work session.

I don't know of a way to remove that. Make sure the Finale window is maximized.

It's maximized.

Try...

1. un-Maximizing the window
2. dragging the top of the window (not the whole window) down to make the window smaller
3. then drag the window up to see if the bottom appears (with the features you could  not see)
4. then maximize again to see if the windows will now fit properly.