Simon and I tested spells and found the following:
Fireball works - But although the note says I lose half my glaze, I do not. I lost a total of three glaze, nowhere near half of what I have.
Blast : message- "you do not know that spell"
Narrate: ditto
Nausea: ditto
Blind: message - "A cold, darkeningg prescence hovers just behind you". Aside from that - nothing happened
Weak Flight: it works ok
Levitation: Inalid Syntax message, but oddly, the spell does work
Serpent: It works, but same as Fireball. Note says half my glaze is gone, it isn't.
Those are all the spells we tested