If I remember right he said that it required twice the Magnesol if the Methanol is still in it. I usually recover a little over a gallon of Methanol from the bio after using 5 in the reaction. (37.5 gallons of oil yielding 31-35 gallons of bio).
Are you recovering a little over a gallon from the bio AND the glycerin or just the bio?
Are you heating and running through a condensor? What temp? How long does it take you?