Thank you very much for your human attitude and help!
@wwebbymaster,
I’m going to mark this as resolved, since it is as far as the plugin is involved.
This is one suggestion that I can make for the screen display if you are able to run SQL statements against your database using phpMyAdmin. When you choose options within the screen_options pulldown, these values are stored in the usermeta table under your user_id and meta_key set to manage{$screen->id}columnshidden
which is, for you, manageedit-ourteachercolumnshidden
. So this becomes
DELETE FROM wp_usermeta
WHERE user_id = nnn AND meta_key = 'manageedit-ourteachercolumnshidden';
You need to change nnn
to your user_id and possibly the table prefix.
This will at least ensure that the default screen processing is run.
Good luck,
Neil James