my 1-6 cyl light seems to have a bit of a short in it...that sensor is known for failures that light on a rossa should only pop up if the cats get too hot which does not happen immideately after startup...sounds like you have a bad/confused sensor or a pinch somewhere in the wiring.
As for the puff of fuel/oil smoke that is very common on a rossa when they sit for awhile as the oil in the bores collects at the bottom of them (since it is a flat motor) and burns off when you start the car.
So as you can see the situation can get pretty grim at times. Barbie has died 5 times. Twice by gunfire, once in the explosion, once by a vicious beating and once when thrown from the Ferrari after it flew off a cliff.