Drop down menu in navbar breaks layout, locks you out of your website.

I'm calling this documentation but it is really a configuration issue. I'm working in Zen, so it might also be a theme interaction problem.

Assigning a nice-menu block in navbar in Zen places the nice-menu below the navbar. This can be fixed by setting Block Title to in admin/build/block: configure nice-menu. This should be in the documentation. Secondly, at least in Zen, you probably want to edit page.tpl.php so that primary and secondary links aren't written to the navbar, assuming that you are using Nice Menus for the primary menu.

The bigger problem comes if you already have a vertical nice-menu in the sidebar: The moment you create the navbar horizontal nice menu, the sidebar menus and other content slide over the main content area, preventing you from clicking on any of the links... including the "admin/build/block: configure" necessary to fix the layout problem. You are effectively locked out of your website. I found that you can regain control by renaming the entire nice-menu module to nice_menus_xxx and reloading which eventually returns control of the blocks page. (nice_menus takes itself out of assigned blocks). Then you can unrename the nice_menus module.

That's hacky for sure.