Did you change the oil or any of the fluids? That would be the first thing I'd do after it sat that long. If you just took it around the block & didn't put any mileage on it the pcm might need more time to relearn the fuel trims. Could also be an issues with the boost bypass valve or one of the vacuum lines to the supercharger. Thats the only things that initially pop into my head. Very nice engine bay btw!