I have a red triangle on one of my iphoto book pages and cannot find out what is wrong. Any suggestions?

Try recreating the page.

When the element you add creates a red triangle... Voila!

What does it indicate? Text outside a box? low resolution photo? ? ? Generally that is a text that does not fit in the text block warning - http://support.apple.com/kb/TS1135#1 - We can not see your computer and only know what you tell us

LN