Type prerequisites are waived in that we as Outsiders can have templates not applicable to Outsiders, but Zaer didn't say anything about other restrictions - I know I wouldn't mind adding the Persuasive Vampire, Psychic Vampire, and Savage Vampire templates at CR +0 despite not being a Vampire, and I'd expect similar stuff would apply likewise.<br/><br/>Now, it'd be 100% legal to have your base creature be a Living Spell, but just snagging the Living Spell template would likely hit a GM speedbump, not to mention rules issues because Living Spell has a fixed CR, not a +CR adjustment.<br/><br/><br/>EDIT: Though you couldn't be a living Wish, because Wish is not an AoE spell.