Just a quick note - you cannot use a "regular" dimmer. - must have one rated for use with a magnetic transformer - this is a lesson learned the hard way!! Dimmer was $60.00!!! Also, this could be the cause of heat build-up in the transformer.
BTW - watch out for voltage drop. 12 volt systems like this dont allow you much wire length-typically approx. 10 feet using #12 AWG wire. Transformer will have to be centrally located and close to fixtures.
