Tinderbox inventory detection or Reset ignite property: I need one!

[DRedshot]

Why not take a look into the code used in the sewer map, where you turn the valves to pour the water into that reservoir. When you turn the handle, the wind blows the torches out. That script might work for you aswell.

Also, is it essential that the cannon is placed on top of objects which can move? Because using CreateEntityAtArea might be the only good solution.