The docs are located at http://www.pagelines.com/wiki
The reason you only see Default and templates 1 to 5 is that those apply to pages you can design. The others are dynamic pages which Wordpress generates in coordination with PageLines Framework. For example, a 404 page is dynamically generated when someone finds a missing page. By using Dashboard > PageLines > Templates, you can add whatever sections you wish to appear on the 404 page, lay it out and structure it as desired, but because you would never add a 404 to a page, like an article or an author's bio, there's no need for the 404 template to appear in setting up the page. The blog page, being a dynamic list of posts only needs sections too, but you wouldn't write your own content to the page. if you did, Wordpress would stop posts from being listed.
These things are all precautionary against anyone making a series of mistakes with their site, thus ensuring you have a professional site quite easily designed. Each of the templates, as you know, can be customized with drag and drop sections and elements that make it simple to get the look you want, quickly, safely and efficiently.