Nice work! I really like the concept and had fun with the game.
1) I got stuck for a while on the deadlock trolleys level, didn't realize you could move the heater. Also found that moving the trolleys wasn't very smooth/responsive sometimes.
2) Doesn't seem to have any bugs for me :)
3) With the deadlock trolleys level, the only instruction was to ask for assistance. Not too sure what that meant.
4) I like the look of the game objects/tiles, but would've liked it if the instructions panel was easier to read and clearer.