Extend the Story - Add a Room

You step on, most mousy quiet, praying that makes a difference. Just as your toes barely clearly the door it slams shut, with a clang that puts you in mind of a pitbull's jaws. In the nick of time you clutch a subway pole that keeps you from being thrown off your feet entirely, even as the train lurches forward in what in a living creature would be called a bloodthirsty lunge. Again, again forward, and then backward, then sideward, upward and downward, to the blue, to the red, and to the gray, and you know you're getting sick, even as there's a lurch, and a lunge, and then an angry coiling inward, and then--
STOP!
Oh praise all hopes, a chance to get your breath; but even as you do, the announcer's horn trumpets: ATTENTION ALL PASSENGERS! GET OFF HERE, OR BE PREPARED TO TAKE ANOTHER RIDE! YOU HAVE 30 SECOND TO DECIDE WHICH GATE! THAT IS ALL!
Uh-oh, better decide what to do.

Go to the back left, the sweet smelling pink light.