The PRO plugin comes with an easy drag&drop interface to reorder your courses and lessons. The order you select will affect how “My Courses” page looks in the student’s dashboard if you use such. It also affects the shortcodes that list lessons in a course.
The shortcodes namastepro-prev-lesson, namastepro-next-lesson, and namastepro-first-lesson to generate easy navigation links through the lessons. There is a checkbox that can automatically replace the old navigation shortcodes from the free version if you have already used them.