Xara's Variants put all the page code into one big file, here http://www.ampedit.uk/blog.htm. It then hides away the Variants that are not in use and reveals the appropriate ized one as the viewport changes.
Your Blogs code is referencing an ID (<div id="dib-posts">). HTML IDs, however, are only designed to be recognised on the first mention; a second one will just be ignored.
You could try creating separate Blogs for each Variant.
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