I just spent 30 minutes looking through posts and can't find my exact answer. I do not want to make a custom menu because I like how nice Atahualpa's page menu looks.

I want to make one of my pages link to our forums, which is not a part of our blog.

Thank you, and here's a cropped image:

Did you try a WordPress menu? The WordPress menu should look the same as the Atahualpa menu.

If I make a wordpress menu how do I enter it in my atahualpa "Style and edit HEADER AREA" like this:

%image %bar1 %page-center %bar2

What would I put instead of the %page-center?

You do do anything there. In teh dashboard->appearance->menu you choose a location for the menu.
Menu1 -> what ever %pages option you pick
Menu2 -> what ever %cat option you pick

Well, look at that, I could assign it as the new pages in atahualpa. As usual, wonderful theme and great help. Thank you!