Now, I will be the first to admit that I know next to nothing about ebooks; however, your comments led me to google the topic using Word to create ebooks and, in the first paragraph, it indicated "using styles to create.....". Here is the link I refer to:
http://www.pcworld.com/article/25361..._an_ebook.html.
Now, if that article is all hogwash and does not work...well, I digress. I just thought was interesting in that you say it would not work (i.e., stripping format) and the article mentions that it does.
In any case, I will step back and hopefully, someone else can help you.