I've done that with my em1 twice, both within the first couple weeks of getting it cuz i had an auto before and wasn't used to having to set the e-brake. The first time I did the exact same that you did. The second time the door was open and it went back into the bushes on the other side of my driveway and got sap all over, no damage that time but I'm lucky there was no car there...yea bad times
Oh yeah, and to add insult to injury.... putting a car in the shade won't keep it from getting waterspots. Waterspots are more likely to form when the water has time to dry. It basically collects dust PLUS there are usually other minerals in the water already. Letting the drops dry on the car will generally leave spots because of what has collected in the water droplets.
Drying the car with a chamios is your best bet. (Of course you wash in the shade anyway.) Even if there are tiny tiny water droplets on the car from drying, they will be less noticable than large water drops that dry.
before i got the turbo, i always put it in first gear along with the ebrake....putting it in first gear became a habbit right away and i always did it, but i did notice sometimes i forgot to put on the ebrake.....now that i have the turbo timer, i can't put it in first gear and i get paranoid if i put the ebrake on or not