The way house permissions were designed, you were supposed to first
define who is allowed in and then use the EXCEPT clauses to make
exceptions to those. An EXCEPT clause wasn't meant to be used alone
since then there's nothing to make an exception to. Unfortunately, a
long standing bug (goes all the way back to when I coded this for Achaea
in college) is that the syntax to grant permision to anyone wasn't 100%
coded. Well now it is! So if you want to grant permission to your
fulcrux or a door or an aether module, etc. then set the permission to
ANYONE and then start listing exceptions after that. For example:

MANSE SET FULCRUX PERMS ANYONE
MANSE SET FULCRUX PERMS EXCEPT ESTARRA

That will let everyone in except Estarra. 😉

Penned by My hand on the 9th of Tzarin, in the year 287 CE.