Book Module---I have spent 3 days trying to edit the book I am in the process of making. None of the changes are ever saved even after I go to the Preview area and create book. IHow do I save the changes in my editing ?

I have been trying to edit my Book and have worked three days trying to save the edits. Every time I leave the LR Program, and return to it, my edits are unchanged. The Adobe instructions say to Save the Book by clicking on the Preview, then Create Book dialog box, then name the Book, and click Create. Every time I do this I have a new name in the left panel with nothing in it for photos. I am frustrated...please help. I am sure I am doing something stupid.