take it back to the dealer .. it needs a proper and full PDI done on it.

battery should not be flat so quick .. there is nothing draining it apart from the clock.

sorry to hear about your troubles.

most of all, you cannot expect it to be as well sorted as a Porsche ..

however, the Cosworth engine does not have much torque under 3500rpm .. but it should not feel like the handbrake is on