Don Croft does not recomend using magnets as there is no benifit as per Carol.
Another report suggested magnets make the orgonite "slippery" for a volcanoe to absorb.
Placing magnets in the corners might cuase the resin to cure incompletly (spoungy)so try to cast them seperatly. E.G. Placing a container with weight in it to reserve the space for later casting.
This will alsow protect your magnets as the high curing temperature might deplete the magnets strength.
Power packs are another option - Copper wraping Xenon light bulbs with a magnet between both wires.
I suggest powering the mobius with a magnet but on what wire to place north or south is the only thing stopping me.