I can't speak for the author, but I think the book title might have more aptly been, "CMS Made Simple 1.6: An Introduction" rather than "...:Beginner's Guide."
The CMS (content management system) itself, CMS Made Simple, is sufficiently simple enough that a beginner could easily produce a site with no knowledge of basic CSS/HTML. If you want to customize the template or output of the modules, then you will need to have knowledge of CSS/HTML and Smarty to accomplish that.