By default, CFiles installs 3 groups:

super_user: This is you. This group can not be deleted but you can create new groups with the same permissions. It is automatically added to every new category to ensure that you always have full access. This group has full access to everything.
default_reg_user: This is the default group that is given to newly registered users. You can delete this group and add your own. You can have multiple default registered groups, but you should always have at least 1 to handle new registrations.
default_noreg_user: This is the default group that everyone is in when they are not logged in. You can delete this group and add your own. You can have multiple non-registered groups, but you should always have at least 1 to handle users who are either not logged in or not registered yet. If you don't want people to have to register to download from a certain category, then you should attribute this group to that category. There should be no need to create more of these groups, but be aware that this group should not have any greater permissions than View and Download. That is, NO Rate or Comment access. You can add new groups with a variety of permissions.

Only 2 permissions are dependent on others. They are: Review Submissions Review Updates
These 2 permissions require that a user also has Add Category, Add File and Add Licence permissions. These 2 options will only appear on the menu if there are submissions waiting, and you have the required permissions and dependencies.

Users can be a part of multiple groups. Upon each category, CFiles collects the relevant groups, and then gives you the highest access available by comparing those groups, with the groups which you are in. Eg.
John is in 2 groups: Group1 and Group2
Group 1 permissions: Browse
Group 2 permissions: Download
John enters Home:Archive
Home:Archive groups: Group1, Group2
Result: John can Browse and Download from Home:Archive

In this way you could create users who have the following rights:
Non registered Browse only
Non registered Browse, Download
Registered Browse Only
Registered Browse, Download Only
Registered Browse, Download, Rate only
Registered Browse, Download, Rate, Comment
Various admin combinations

The user and group management has been designed to be easy, but scalable to the needs of a large download archive which might need multiple admins with varying levels of access.