I followed the advice of wtatumjr this weekend, as I had not melted the which in over a year. As it turns out the switches were not reacting well to the witch "hits". It took me about two hours to figure out how everything was connected, take it apart, find the parts that I dropped and put it back to together. As it turns out I ended up moving the microswitches back (away from the witch). Ultimately I had to re-shape the arm of the right microswitch (it was curved). I did not need to adjust the metal plate--I suspect all changes can be applied to the switch arms.
I melted the witch in next game I played. Hallelujah!