I read that to be published in ePUB format that all tabs should be removed. This sounded like an onerous task, and it is, but I would recommend it anyone, even if they are only planning on submitting to Amazon. Being forced to go through the entire manuscript with the format visible proved to be very useful, allowing me to clean up many little errors that could cause problems when viewed on a Kindle. For a 90 000 manuscript, it took me about 2 focused hours to take out all the tabs and clean up all the other little mistakes I would have never noticed before.
So, I uploaded the newer version to Amazon and soon to Smashwords. I feel bad for those people who purchased the ebook already because it wasn’t putting it’s best foot forward.
Moral of the story: take the time to be anal, even if it’s not in your nature.