Using Edocman obviousley (Duh!) and also using SP Page builder for page layout control.
What I would really like is to have a left colum with the Category Tree listed in it, and when a link on the tree is selected, Id like the contemt to open in the right colum.
Actually, i am not sure that SP Page Builder can be used to setup the layout like you want, but in my mind, you can setup menus to layout: Edocman Category and select your categories for those menus in parameters form.
Then, you can assign module: Edocman Categories tree view in those menus (Left position)
Thus, when you click on category link, that category page will be opened and the tree module is still shown on left hand side