I just realized that I…
I just realized that I didn't know whether when Cafe Press said '52 pages', they meant 52 sheets of paper, and therefore 104 pages to work with, or 52 pages and 26 sheets of paper. I have dropped them a note to ask, but I thought I'd mention it here, in case any of y'all are working on Cafe Press books.
I heard from Cafe Press — 52 pages means 52 pages of content, and therefore 26 sheets of paper. You have been warned.