I have always made ePubs with bits inserted to make it ready for Kindle conversion.
This goes into the Metadata section of the Content.opf
<meta name="cover" content="my-cover-image"/>
This goes into the manifest section
<item id="my-cover-image" href="images/Cover_kindle.jpg" media-type="image/jpeg"/>
This goes into the Spine section:
<itemref idref="cover" linear="no"/>
This goes into the guide section:
<reference type="cover" title="my-cover-image" href="images/Cover_kindle.jpg"/>
<reference type="toc" title="Table of Contents" href="Contents.xhtml"/>
And, finally, I add a Cover_kindle.jpeg into the Images folder.
Now, doing this, I've never had a problem getting the epub through epubcheck.
But now, since they've updated it, I errors out.
I've been ignoring this, as I know the files are correct. But it's just annoying...
Does anyone have any ideas how I can get around this?