Menu Macro scope and sub-wiki usage are in conflict

Context :
The menu application allow you to have an horizontal menu used on all wikis (main and subs).
You want to have your own horizontal or vertical menu done with the application on sub-wikis.

Issue :

• I can't remove the application from any wiki without breaking it everywhere

Expected result :

• Be able to delete the Menu application from a sub-wiki without having to resave or reinstall MenuMacro on an other wiki.

Seen problem :

• Menu.MenuMacro scope is set to Global on both wikis