You were right about the system slowing down. I had set theme designer on when I was trying to debug the failure of icons for text field editing to display. (It didn't help, since that issue was bad Mac upload end-of-line characters, but I forgot to turn it off). However, I apparently managed to work during an assault on the server, which overloaded the database. The token errors where caused by queries timing out; a few minutes after I sent the message, the Moodle started reporting that the database was either overloaded or down. About two hours later, everything cleared out without any other intervention, and now it all works.
So: initial issue caused by bad Mac upload; fixed by using the Moodle site zip file and manually updating all modules.
Secondary issue (some login failures) was due to using the wrong config.php file specifying the wrong DB; that was fixed by putting the right one in place.
Third issue (DB failure) caused by overtaxing the DB; that fixed itself. I must say I'm impressed by mariadb's hardyhood.
Thank you for your help. We've had no problems since Sat night (our time)..so nearly 40 hours working. I'd say we're good.
So: initial issue caused by bad Mac upload; fixed by using the Moodle site zip file and manually updating all modules.
Secondary issue (some login failures) was due to using the wrong config.php file specifying the wrong DB; that was fixed by putting the right one in place.
Third issue (DB failure) caused by overtaxing the DB; that fixed itself. I must say I'm impressed by mariadb's hardyhood.
Thank you for your help. We've had no problems since Sat night (our time)..so nearly 40 hours working. I'd say we're good.