Try this:
For content.opf add:
PHP Code:
<meta property="rendition:layout">reflowable</meta>
<meta property="rendition:spread">auto</meta>
<itemref id="titlepage" properties="page-spread-right rendition:layout-pre-paginated"/>
For the cover page add:
PHP Code:
<meta name="viewport" content="width=684, height=1024"/>