title_body: Exporting epub fixed layout
upvoted_answer: ePub is just a whole bunch of HTML, some metadata, and CSS. So, you have the same rules as with any HTML page.
  
  
  You can't force any browser to display a page the way you want it. Your "fixed layout" is at best a suggestion.
  If you specify a typeface, and that typeface is not available on the client device, it will be ignored. You can ensure that the font is available by packaging it in your ePub, but you'd better be sure you have a legal right to do so! If you aren't including the font in the ePub, then you have no way to force the client to use it.