Ferrari 458 - Starting/Running Issue

After leaving my 458 in my apartment (second home) garage for almost two months. Being on a trickle, it fired up willingly, revving easily, but when I paddled into first, the engine died. Feathering the gas was useless as the rpm's continued to drop until they reached 400, and then 0. Several more attempts resulted in the same. Ferrari Roadside assistance arrived and simply drove the car out of the space, like the achy tooth at the dentist.
I drove the car, which was then running well to the local Ferrari dealership whose diagnostic testing showed nothing wrong. The next time I drove it, I just put it into first and immediately drove out of the space as the roadside assistance representative had done. Everything seemed fine.
I did not drive the car again for another month. At that time, I allowed it to idle for 30 or so seconds before driving out of the space. When I tried to move the car, the problem, failing to continue running, repeated itself, and it died half in and half out of the space. Several attempts to restart resulted in the engine running then dying, but I was ultimately able to utilize the few 100 rpm's available to nurse it the eight feet back into the space.
The space is on a sideways incline with the entire driver's side being at a level of about 6-9" above the entire passenger's side. The gas tank is 1/2 full. I would value any insight into this problem and a cure. I wonder if: (i) the gas in the tank is inferior; (2) the gas tank has water in it; (iii) the injectors have become clogged; (iv) an automatic fuel management system, if any, is malfunctioning; or (v) the angle at which the car is parked leaves the engine unable to suck out sufficient fuel until it is driven away from the incline?

 

I would like to thank all who responded and tried to assist. I have solved the problem. The car sits on an incline in an underground garage. Once it is off the incline, it runs perfectly!