Need help with understanding TeamWars –> Settings

Can anyone who has messed around with the TeamWars be kind and willing to explain in a paragraph or so what exactly is going on in the Settings section? Specifically the User Access sub section… I just can’t wrap my head around what exactly it’s for and what/how to use it. Selecting check boxes and hitting apply, etc etc does not seem to ‘do anything’ best I can tell. But again, I’m not so sure what it’s meant for either.

Thank you much for anyone who can chime in here.

Cheers,
-Q