Ah, Black Blood Cultist...love that class. Anyway, you're right, that link I posted seems to suggest you can't use natural attacks with Flurry. Frankly, that's stupid, and thankfully the FAQ contradicts it!
"Can a monk who has natural weapon attacks (such as a
centaur monk) attack unarmed and still use his natural
weapons? For example, let’s say he’s a 4th-level monk. Can
he use a flurry of blows and attack at +5/+5/+0 unarmed
(plus other bonuses) and then at +0/+0 for 2 hooves?
If the creature normally is allowed to make both weapon
attacks and natural weapon attacks as part of the same full
attack routine, the monk can do the same (making unarmed
strikes in place of weapon attacks). Since a centaur can make
two hoof attacks in addition to his longsword attack, a centaur
monk can make two hoof attacks in addition to his unarmed
strike attack (or attacks, depending on his base attack bonus).
The monk can’t use his natural weapon attacks as part of a
flurry of blows, but
he can make natural weapon attacks in
addition to his flurry. Such attacks suffer the same –2 penalty
as the monk’s flurry attacks in addition to the normal –5."
From the main 3.5 found here:
http://www.wizards.com/default.asp?x=dnd/er/20030221a