Interesting, I see what you mean and this is certainly a first time I've seen this sort of layout!

I didn't have any problems with your file - http://robert1.xara.hosting/ayr/ , are you deleting the other pages after it has been uploaded?

Also, if the other pages on your main variant aren't in use so to speak, I would suggest un-sharing the elements there (don't worry, they should remain on the mobile variant), then delete them. This will reduce the amount of files that Xara uploads and also make the page more lightweight, although depending on the viewport, those on a tablet who view your website in portrait and then switch to landscape may see a blank page.