Unfortunately, downloading the sessions as PDFs under the Program Reference Tools tab and saving them is the only way that you can re read the sessions. Once you have read them, you are unable to go back and read them again. In saying that, our team is working on a new and improved version of the site which will come out in the near future, and included in the new site will be the ability to re read and skip/jump sessions.
I'd like to know how to do this too. If it's not possible, then it would be great if it could be made possible because this is a fantastic program and the ability to re-read previous sessions would be a big advantage. The only way I've found of re-reading the material is by downloading the sessions as PDFs under the Program Reference Tools tab in the Session Diary.