Haha, what an idea. xD Kudos for a really creative take on the theme. The only critique I have is that it's difficult to gauge how well you are slowing down the trolley. I have a feeling the game quite suddenly proclaimed I've stopped the trolley. During that time, I felt like I wasn't doing particularly well. Maybe I'm simply not understanding how the game detects its win condition.
Nonetheless, crazy idea. :D