Very minor cosmetic (but misleading) bug:
In M2P v18.104.22.168, the visibility hints as shown to admins apparently don't take into account the 'access' attribute into account. So, for example,
[ms-protect-content access=no silent=yes id="$ID_NO"] Content for non-members [/ms-protect-content]
The visibility hints says that "Content for non-members" will be shown <b>only</b> to members of membership level $ID_NO ("Other uses will see nothing"), when in fact, it's the other way around.
The shortcode functions correctly, however.
(If it matters, we also have multiple memberships enabled, and in this case, $ID_NO is a comma-separated list of membership IDs.)