If you’re looking for a really simple way to navigate a lot of files in a PDF Portfolio and don’t need all the bells and whistles of the default layouts, check out “Tree with Preview”. I’ve removed everything except the most basic file navigation features making the preview window as large as possible and highly responsive.
Because only PDF files can be displayed in the Preview window, you probably don’t want to use this one for source files. I also set this one up so that folders can’t be selected. If you click on a folder the first child file of the folder will be displayed. If, like the sample file, the first item in the Portfolio is a folder, the first child PDF file will be shown.
You can use the Custom Components panel to set the size of the text in the list and the Color Pallet panel to control the text color. In this layout, the “Text” color is the color of all the items in the list. The “Accent” color is used for the selected item.