Ok, I'll illustrate my forums structure, as it's similar but not identical to yours:
- Tab 1
- Category 1
- Forum 1
- Forum 2 <-- Only Admins and Mods can see
- Forum 3
- Category 2 <-- Only Admins and Mods can see
- Tab 2 <-- Only Admins and Mods can see
Tab 1 is a mix, some of which are category based restrictions. Atm the code shows the category header (wrongly cos vB wouldn't do as standard), but rightly doesn't show the forums.
Tab 2 is ideally Admin only, and it'd be nice to allow that only to be visible to admins.
I hope that makes some sort of sense.