I'm developing an ePub 3 textbook with fixed page layout in portrait mode (this is necessary because the many figures in the book have to be aligned with specific text). ADE displays the textbook perfectly on my MacBook Pro. When I open the textbook in ADE, initially it functions well and I'm able to advance through the pages continuously using either the arrow keys on my keyboard or the arrow icons on the ADE window. However, if I use a page link in the text, the link works, but the advance by keyboard arrows or icon arrows stops functioning. I can get it to allow me to advance one page by clicking on the displayed page, but it will not advance continuously as it did when the book initially opened. The only way I can fix the problem is to close and reopen the book. Then the advance works normally until I use a link again which results in the same problem. The textbook was developed using Jutoh on a Mac. Any ideas on how to correct this problem are welcome.