How to re-perform?
1. Create guest user access level as described here:
docs.joomla.org/Access_Control_List/1.6-...nu_Items_and_Modules
2. Create two modules sclogin on two different module positions.
3. Assign to both user access "Guest"
The bug:
When the user is not logged-in, it is expected that both modules should be displayed.
The result:
Neither of the modules is displayed.
When assigning one of the modules to another access level, both work fine.