Quick question submitting ibook in the Epub file...

Hi Everyone -

I am looking to publish with ibook, and instead of using their template, I want to make a simple book using the same dimensions as used in the templates, but submitting the book via epub format from Apple Pages program.

I do understand that a separate cover image is required to submit to the ibook system, used for the store itself, but because I am NOT using one of the templates will I also need to make the cover in the file itself? Then shall the cover be the very first page? The reason I ask is simply because the ibook system is probably used to their templates in which everything is pretty much set up in a manner that is fluid, so because I am choosing to send an epub version instead of using a template I was curious as to any factors I have to consider before submitting the file.