It appears the author has died (or something worse). Perhaps Envato does not know either. Anyway.... this was one of my favourite plugins, as Im sure it was for many other purchasers.... but the author is not supporting this or his other Envato offerings, and THE FLIPBOOK PLUGIN DOES NOT RUN ON THE LATEST WORDS PRESS, and it is not likely to ever do so :-(
Stopping support is bad for business not everyone is knowledgeable of codings. Atleast offer a forum for self help if you can not help anymore or just discontinue the product altogether and not get people to buy and not get answerrs for simple issues.
Quick and easy to set up. Looks great on front end. Some back end bug fixes: page thumbnails do not populate (all thumnails show the book cover); also page numbers do not show while pages are collapsed in edit mode (all read "0"). Overall I do recommend.