I'm able to add folders for deletion (options-include) but I have noticed an " *.* " icon in a type-able box that appears at the bottom left part of the "add folder" dialogue box. Does adding more asterisks mean the folder contents get deleted more securely ?
If you select a folder and the file mask is (*.*) then all subfolders will be included (The technical term is 'recursive'). If the file mask is changed to something else (*.tmp), then any subfolders within that folder will not be included. (The technical term is 'non-recursive.')