Here are two links to two pages I found helpful when porting to the new Smugmug. The first link explains what Content blocks are and how they can be customized when building the blocks for your site. There are eight types of content blocks.
NAVIGATION: Page elements that help your viewer move around or search your site.
Menu – Build a navigation bar, with links to other pages on your site as well as to any external sites that you’d like your viewers to visit (e.g. blog)
Galleries – Display certain Galleries
Folders – Display particular Folders
Pages – Display certain Pages
Folders, Galleries and Pages – Display all of your content
Breadcrumb – add a breadcrumb to reveal the links between your homepage and the page being viewed.
Featured Events – (Pro) Feature an event on any page that you create
Hierarchy and Folders
This link shows that the NEW SmugMug allows for a total of seven layers of pages.