Not that I can really be of any help with your actual formatting problems (I'm not deeply into ebook formats), but:
You could produce a variant of the file which only contains 2 or 3 pages, and link to that one. This should be ok for the author, yet would still allow people to take a closer look. On a side note, this may not be the best forum for your request. You will probably find more experts in the "E-book formats" subsection of MR.