Applications :: Comic Life Page Size For Graphic Novel

I'm using Comic Life to write a graphic novel. I'm having trouble formatting the page to the same size as some reference books I'm using (Watchmen, a couple of other paperbacks the same size). I have computed the page format size based on the 72 pts per inch to what appears to be the standard 10.25 x 6.625, but when it prints it's significantly smaller.

I realize I need to create the book in a format size that will be available with the book on demand printing I anticipate using- The Watchmen book appears to be roughly 10.25x 6.625, the size listed on Lulu for Comic book size. How to set up comic life page to be same size?