Wow, that sounds frustrating. I don't have an iPad but if I were you the first thing I would do is log in to bn.com and archive the problem book, which should tell your Nook app the next time you open it to get rid of the copy of the book on your iPad and not redownload it until you choose to unarchive it. When you unarchive it, a fresh copy will be downloaded, which might fix the problem. If it doesn't then there is probably something wrong with that particular book and I would let B&N know about it. Digital Support is option 2 at 1-800-THEBOOK.
If the archive trick doesn't help then hopefully someone who actually has an iPad/iPhone will have some other ideas for you, but otherwise you can always try calling Digital Support.
To prove how clueless I am, what's the tiny plus sign meant to do? Not cause it to go into fits, I assume.
Hi, and thanks so much for your input. Actually I had tried just about everything, including deleting and re-install the Nook app. I did finally call Nook Tech Support and they were unable to resolve the problem either. They finally refunded the price of the eBook and I have in the meantime re-purchased it via Amazon for the Kindle app on my ipad... Not the best of solutions, but at least I can now read the book.