I have this same problem on my mmr. One of the blue
solenoid board has a short in it. When i would power the game on it would either blow the fuse or engage the right flipper. If the fuse didn't blow it would smoke the coil. Tech support had me move the blue board over to another spot and see if the problem follows. Once I moved the board the right troll will pop up. I need to buy a new board Just haven't gotten around to do it. I always watch the game when it boots up now to make sure I catch anything energized until it's bought and replaced.
Also sometimes when I boot the game up a get a communication error(thought it was the cat cable but it's not that) or the display will be a solid color. Just have to reboot it. Until it works.