I would find Blitz a bother. I think it's just easier to create an ePub 3 eBook but not to use CSS code that doesn't work in ePub 2. And in the HTML, don't use classes with <section>, <header>, or <figure>. And don't use <figure> where a <div> would be used in ePub 2. Also, you will need an NCX ToC to keep compatibility with ePub 2.
If I wanted to create an ePub 3, I would use the plugins for Sigil that help in creating ePub 3.
|