My blog in Propulsion is allocated on a page called "Magazine", which should be splitted up in "Blog" and "Forum". In the theme options, I choose "Magazine" as Blogpage. Theme options default page layout is "right sidebar".
To have than on that "Magazine" page an overview of all blogposts with a sidebar, I generated a custom template with a right sidebar by using the template builder. Now, I wanted to have a view on the single blogpost without having a sidebar. For that reason I generated again a custom template without sidebar (Fullwidth). But the sidebar still shows-up.