Hit 'em high.
Hit 'em low.
The first turn it actually moves from the bottom to the spawn, so there will be a double zombie spawn the first round, not a fire.
Ah, I'd read the original rules a while ago and only gave a cursory look over the newer version. Small detail I forgot.
You are confusing two things: the fire trigger and the fire spreading.
The fire only starts when it is actually triggered by a spot on the darkness track (that is triggered at a later point in the game).
The spreading will do nothing if no fire is currently active.
Again, looks like I missed this (now that it was pointed out, I feel silly for having been so obtuse...then again, I was reading it at work, which may have something to do with my inattention...)
Thanks all for the replies!