4. Tap on Open in "iBooks". iBooks then takes a few minutes to load the book. Eventually you will see the title page and be ready to open it up.
Try the above link first and wait for 15 minutes before going nuts. If that doesn't work, try holding down the nearly rectangular button on your iPad for >10 seconds. This will restart your device. Then you can try again. It is a good idea to check Settings to see that you actually have enough spare disk space for the book (>400 MB). Another possible trick is to go to Settings, and then Safari, and clear the short-term browser memory.
We don't know why you would want it, but HERE is the PDF version. You could read most of the text on it, but the widgets will be flattened.