The program for this was simple: make the catapult throw the marble and then come back down. The program may have been simple, but the building was not so easy. First, the catapult would throw the marble near the ramp not ON the ramp. This was fixed by lining up the ramp exactly with the catapult. One of the hardest challenges was getting the platform to stay up and only come down when the marble landed on it. The platform would either fall down before the marble landed on it and pull the string too early or the marble would land on the platform and it would not come down at all. This was fixed by getting the right amount of weight on the platform so it would stay up and come down when the marble landed on it. The most annoying challenge was when the marble would fall down the chimney along with the dice and roll off. This was fixed by adding a beam at the end of the ramp that the dice could slip under but the marble can't.
If you really liked this dice roller, I will be posting again in less than a month with something better. :)