Custom Menu Problem for Newbie

I believe that you will need to do some coding to get what you want.

You should create a Child theme to make your changes. If you do not, all of your changes will be lost if you update your theme.

You will need to register a new menu location with in your functions.php. But be careful, if you make any errors, your site will be unusable and you will need to use ftp to correct the error. The code below goes in functions.php (possibly without the opening and closing php tags):

<?php
   if ( function_exists( 'register_nav_menus' ) ) {
      register_nav_menus(
         array(
           'bottom_menu' => 'Bottom Menu',
         )
      );
   }
?>

You will need to modify index.php by adding a line of code between these lines:

<?php endif; ?>

   </div><!-- #content -->
</div><!-- #primary -->

like this:

<?php endif; ?>

   <nav id="bottom-menu" ><?php wp_nav_menu( array( 'theme_location' => 'bottom_menu' ) ); ?></nav>

   </div><!-- #content -->
</div><!-- #primary -->

You will also need to edit style.css, copy all rules containing #access, and change #access in those lines to #bottom-menu.

That should keep you busy for a while!