I am in need of some help repairing my BTTF game. It has been working great, but last week I turned it on to play, all the lights came on in the playing field and back board, but no sound, score, or pinball would engage with pushing the start button. I am a new owner of pinball machine, I love and would love some help getting it fixed. Any thoughts on a problem?? The original owner I purchased it from thinks its a fuse or lose wire?? Also, how does the back glass come off? I do not want to break it. Please help!! Thanks!! Nikki