As far as the lockup goes if one of those ROM chip pins is not making contact it will screw something up and cause issues like what you're having. I pulled, cleaned and reinstalled every chip on mine. I thought I had checked every pin for conductivity. Must have missed one and it wasn't making contact. Game wouldn't boot into attract mode. Found it. Cleaned and reseated it again. Checked all pins for conductivity again. Game working. And when I say conductivity, I don't just mean chip leg to socket leg. Check chip leg, follow trace to next component and buzz it there.