Another glitch I encountered with Createspace involved the book's interior.
I'd downloaded and used the template they provided for a 5.5" x 8.5" book—and, because I can be a little obsessive-compulsive (especially with this, my first publishing effort), instead of merely copying the document's settings, I inserted the book's text into the template. I truly did use their template.
I felt very secure in my knowledge that everything would fit just fine on the printed page(s). Plus I was able to get alternating headings (author name and page number on left-hand pages; book title and page number on right)—and no heading at all on chapter openings. I haven't quite sorted out how they did that. (But I will. I like the look very much.)
Yet when I uploaded the PDF, what do you know? They (or their automated program) found that the artwork on every page was outside the potential trim lines. And then their program recommended I set my margins—to even less than I had (thanks to their template).
I suspect that in this case (and perhaps that of the cover as well) there is some sort of glitch and the program was misinterpreting the PDF image of a text page as being an "image image" (such as a photo or illustration). It wasn't correctly differentiating blank space from text-filled space.
This may have come up again when I submitted the whole book and ordered a sample copy, but since it seems like sheer computer-generated craziness, I don't expect any surprises. (Not like my concerns regarding the cover; see previous post.)
I'd like to hope that their template led me to make good choices on margin and text sizing, and that my choices of font and placement look as nice (to me) in reality as they do on screen. And paper color. I went with white after reading other comments on the internet. Hopefully it won't be too blinding.
The page count comes to about 424. It'll be interesting to get the feel of that in the hand. I'm not a fan of the 6" x 9" trade paperback size—not exactly sure why—but I'm not a fan of a fat book, either, unless the pages are thinner than usual (so they'll stay open without my having to crack the spine).