Scrolling after closing navigation panel shoots to end of book

HI,

I use Adobe Digital Editions every day for the DSM5. If I use the navigation panel to find an area in the book in the table of contents or by bookmark, then close the navigation panel, then try to scroll to the next page, I'm immediately taken to the last page of the book. I can't get to the next page either by mouse nor arrow keys. Essentially, the only way I can do this is to scroll through the entire 992 page book to the page that I want, then I can scroll to the next page, or leave the navigation panel open all the time. Given that with the navigation panel open, I have to constantly scroll left/right on the page because the text doesn't reflow nor fit all on one page with the navigation panel open it's extremely frustrating.  I'm on Mac 10.11.3 with Digital Editions version 4.5.126234. I had this same problem on my last laptop and did a clean install, so am pretty sure it's not just my system. Does anyone have a fix?