You may also select this option and still begin the reading in a desired location within the book, by using the chapter advance button of your respective media player (the same button used to advance to the next song if you were playing a CD).  The book will be advanced the same number of chapter files forward or backward, according to the number of times you have clicked on the forward or backward buttons.  Once you find your desired starting point, the narration will continue non-stop from that position, until it reaches the end of the book (or until you stop it, of course).