OK, this is what worked for me
In article-templates/manage.php change
} elseif($_POST[‘action’] == ‘new’) {
wp_write_post();
}
to
} elseif($_POST[‘action’] == ‘new’) {
unset($_POST[‘post_ID’]);
wp_write_post();
}
Which seems to now allow me to add new templates. I can’t seem to delete them, but that isn’t a deal-breaker for me