I really couldn't say with any high degree of being aboslutely certain but there is a bit of a clue in your original question...
"there was a popping sound from the dimmer switch"
If you were previously able to have the lights on from the conventional switch with the dimmer turned completely off - and the lights now no longer work from the ordinaty switch - I would begin to suspect the transformer.
If the conventional switch controlled the dimmer - i.e. conventional switch has to be set to on for dimmer to work - then I would suspect the dimmer.
P
November 2009