When you want to override the edit permissions of an area but you don't want to use Advanced Permissions, just use the following code:
$a = new GlobalArea('My_Site_Name'); $u = new User(); if (!$u->isSuperUser()) $a->showControls = false; $a->display();
In this case only the Super User is allowed to edit the Area in the frontend. To create a own filter with user, groups or groupsets check this page: http://www.concrete5.org/documentation/developers/permissions/users/
Hope this helps!