I'd just like to add my two cents to this topic, and hopefully save someone a whole lot of frustration. I ordered a copy of the CMBB strategy guide through Direct2Drive as well, and have had a completely negative experience. It's no longer a simple .pdf download. They apparently now require you to use software called Adobe Digital Editions, and which so far I have been unable to get to work for me.
It has been three weeks now and I have still not been able to configure this software correctly so that I can actually read my book. Direct2Drive's customer support has been unable to help me and they directed me to contact Adobe's customer, who also has not been able to help me. I paid for this book, downloaded it to my computer three weeks ago, but due to some problem with activating the software, I can't actually open my book to read and/or print! It has been a very confusing and frustrating experience, and I hope Battlefront reconsiders who they use for similar services in the future.
That having been said, I've requested a refund and if anyone knows of a good place to try to purchase another version of this book, particularly the original printed version, I would be extremely grateful!