Unregistered/Unauthenticated Users can no longer see anything, are forced to create an account

We are running v10 B2, and some strange things happened.  First, the entire feed disappeared and it looked like some modules seemingly uninstalled themselves (I swear they were installed a week ago!) and secondly, no one from the public (unregistered users) can see anything on the timeline now.  They only get a create account/login page now that looks like the attached.  We have no idea where it came from.  Permissions say that they have the ability to view posts, discussions, etc., like it should be, but they don't see anything.  We reinstalled the modules that had been "uninstalled," and we have the timeline back for registered users, but the public side still only gets this login screen.  We have no other levels defined yet at this point.  Most everything is still default from the installation.  We're really stumped.

I note that a number of modules say version 10.0.0 or 10.0.1 or 10.0.2.  Shouldn't at least all of the UNA Inc modules be 10.0.2?  Maybe this is the problem.  But there are no updates available, and the dashboard shows we are running version 10.0.0-B2.