I'm not sure if this is intentional, but there are a couple codex entries missing from the bosses section. All duplicates (indomitable vicious, Ke'eeng Ra'at in the silver challenge, and super duper meat man). Aditionally, the page with Ra'at Sied is unfinished.
EIDT: Oh yeah! You should probably remove the class challenge section from the monster classes. It always catches me off guard and is a little distracting.
I speak chaos.