what does the RED triangle alert mean?

Putting together an iphoto album for my grandmom for Xmas. I finally finished, but there is a red triangle on the cover over the title. There's alot of info about yellow triangles but nothing about red. When i click on "Buy the Book" the message says "Your book appears to have text that doesn’t fit. If you continue with this book order, any clipped text may cause the order to be canceled at a later date. To edit the text before ordering the book, click Cancel." I've tried shrinking the text size in Settings and even removing all the text, but the red triangle/exclamation point stays there. Ughh...this thing will never be finished!