Hi,
Thank you for the details!
Generally WordPress database tables are case and accent insensitive by default. These issues in most cases need to be resolved on the host, by converting the underlying database to a case and accent insensitive one (which should be the default). Some things can be forced via the plugin, I will check if there is anything I an do.
Unfortunately I can’t login. Both the admin and the wp-login pages give me an internal server error when I try to reach them. Can you please check?