That MAY have been the problem. However I deactivated, then uninstalled XCloner to try another backup plugin, which does not do what I need.
So I reinstalled Xcloner, activated it, and went directly to Settings to change the admin password. But this fails, with the error:
Not Acceptable
An appropriate representation of the requested resource /interim/wp-content/plugins/xcloner-backup-and-restore/index2.php could not be found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Via file manager, said file exists… and is writable by owner & group, though not by world.
Did NOT see this error on the first install, and I was able to change the admin password.
Frustrating!