[smw]

I did notice that when I'd go into annotation mode, the page would go full screen and then would go back to the incorrect narrow view when I'd exit.  I thought it might have something to do with the crop settings as one time I reset the crop and that fixed the problem.  However, that didn't always work.

This matches my experience exactly.  The problem seems to appear and disappear almost at random, with no correlation to anything I've been able to find; many actions usually seem to fix the problem, but the fix is always only temporary.

...but annotation mode always displays the page correctly, and when a page with the problem is edited the annotations stay where they should be even when the rest of the page reverts to the narrower display.

I should note that I haven't been keeping up with the updates on my tablet.  This is the first update I've taken since last fall.  I did notice that a number of config settings got reset after the upgrade so I've been having to fix a few things.

This too matches my experience, in the sense that it confirms that the problem has been around for a while.   I always update to the newest version as soon as it becomes available, but I've been seeing the problem since at least November (and possibly earlier, but November is the first time I'm absolutely certain of).

I did notice that a number of config settings got reset after the upgrade so I've been having to fix a few things.  Could that be causing a problem?

My guess would be no, but it's only a guess.  For what it's worth I haven't noticed any of my settings being lost; perhaps that happened to you because you jumped several versions at once?

Is there an option to go back to "factory" settings without losing the whole database?

Under "Other Settings", there's an option called "Reset Settings to Default".  I've never used this, but I'd be astonished if that wipes out your library.  Of course, it never hurts to take a backup first anyway.