C7 Z06

Hi all,
As most of you are likely aware, and likely tired of hearing about by now, I just picked up my new Z a couple days ago. I noticed leaving the dealership the engine was not crisp from idle. It had a hesitation and the sound of air getting sucked in. My 15 was similar but not so pronounced. It is much better now but still requires a bit more attention taking off at the lights with the M7. Otherwise the engine seems fine and feels responsive above idle.
I have 200Km on the car now and today gearing down approaching a red light a big cloud of blue/white smoke belched out of the car. It smelled like fuel and came with a bit of a backfire. 3rd to 2nd RPMs 3000ish on the downshift.
Wondering if the computer is still learning or what? It never did it again during the rest of the 80km trip of highway and city.
Anybody see this with their C7 Z06 new or otherwise?

Derek