The Trang proof came today, and I realized that the placement of many of the chapter numbers causes them to get lost in the book's gutter (tricky, because it looks fine as a layout printed on a large piece of paper--those have no gutters). So I decided to fix that, plus one or two other little things.
We'll see how that goes--with the exception of one minor correction, the only thing I did to the interior file was change the placement of the chapter numbers. But CreateSpace's automatic error-checker freaked out, claiming that every sentence starting with an italicized f was now outside the margins. I finally just clicked "Ignore Errors and Submit"--we'll see if I get anywhere with that.