Many years ago there was a pc game that me and my mates would play at dinner times at school if it was raining. The object of it was to (I think) press a button at some point on the screen. When it started all you had was the button and a starting point and then you had to add things like a gun to burst a ballon which would start a fan blowing to set a ball rolling into something else and eventually the button would get pressed. Sort of like when the gate gets opened in The Goonies!
Does anyone know what game it was? Or was the description to confusing?