The second setting in Advanced Settings allows you to force the order in which Topics and Tests are completed by a user in an individual Subject.
Topics and Tests will be locked until you complete the one before it. Here's how it looks for a user:
If a user searches for content that is "locked" for them, their search results will look like this:
They can still click through to the Subject, but cannot click through to the Topic or Test that is locked until they complete the previous Topic/Test.
Admins can navigate to any Step in a forced order Subject as long as they are in Admin/Edit mode. If an admin switches to self mode, they can view all Topics, but can't hit "mark completed" until they complete the previous Topic/Text.
If an admin needs to navigate through uncompleted topics in Self mode, they can navigate using the side navigation.