Very fun game, especially for a 3 hour creation!
The main constructive criticism I have if you work on it any more, or for future games, is to make the UI a tad bit more intuitive/natural to use.
I would move the Start button up to the middle of the screen instead of way down at the bottom, and also make it where once you place all of your torches it automatically presses the button for you, and possibly has a 3...2....1 countdown before starting.