So, the (migrated) Kunena forum has a "root" category that is normally not used. In Kunena, its not allowed to post. But here I see its an available choice in the "new topic" dropdown.

I need to make it NON-POSTABLE by everyone.

The problem is, when I remove its posting permissons, it nukes the permissions for ALL THE SUBFORUMS ( which inherit) ...

AND THEN, when I set the those sub-forums  to have their own appropriate posting permissions, they are STILL mysteriously blocked ( no "Start a Topic" is visible...)

Is there a workaround for this?  Permissions are stuck "LOCKED" ( see below)

hmmm - PNG attachments not working right ?  I had to add it twice before this one appeared...