I've watched it, but I still don't understand why that thing exploded.
It's a problem inherent in flash. Flash is pretty weak when it comes to doing a large quantity of complicated mathematical equations. I'm not even sure how they optimised it for this game. I've seen quite a few exploding contraptions poking around in the player built solutions, and I've made a few myself. The nearest thing I can tell, after making a few is that it has something to do with how the program handles unbalanced torque. It basically stops being able to figure out what the fuck is supposed to happen, and goes bat shit nuts. (ie: if you are causing torque in different directions at once)
Whats stupid is that, even after having beaten every single free map, I find myself going back and setting myself new challenges to accomplish on them; such as the brute force machine on "Awash" or the one where I wanted to land the marker in the goal without it leaving in "Down Under."
I keep taking breaks from playing the Warhammer beta to play this...
Also, people (no one here that I am aware of) need to stop publishing every god damn thing they make. Hence, the user created solutions are crap flooded with 500 of basically the same fucking machine, and it's harder to find ones that are actually somewhat interesting.