Nook bugs

OK, everyone, I have a question.

I've put Kea's Flight up for sale as a NookBook:

http://search.barnesandnoble.com/Keas-Flight/Erika-Hammerschmidt/e/2940012378828

I submitted the same ePub file that I submitted to Lulu (it uploaded there successfully, and it reads fine on my iPod touch). When I chose the Preview option on the Barnes and Noble site after I uploaded it, it was perfectly readable. But when I try downloading a sample from the product page, I get an epub file full of unreadable symbols.

Maybe they change the ePub file so that it can only be read on a Nook? Do any of you have a Nook you can test the sample on? If you have any insights that may help, please email me at humanalien at gmail dot com.

Thank you.