I have published a new version of the book:
1. New chapter showing how to use external widgets to manipulate a calendar instance: datepicker for navigating and checkbox for filtering.
2. Added code in the database persistence samples to save updates when resizing or dragging events.
3. Fixed bugs in code samples from the database persistence chapter. Also updated Web2py sample project with those fixes.
Buyers from previous versions will get these updates for free. Interested developers can get their own copy and future updates will be free.
Thank you all for your support!