Parking mode are time lapse video so it is always recording, with a range of settings to choose from, but for thermal reasons it are not full blown video like the normal recordings.
To start with it is all pretty basic, but i think it have been mentioned that when the basics are in order the company will start to look at what customers would like.
Your alarm should not be set off, at least i have not heard of that happening to any of the users already out there.
12.2 Volts cut off is the lowest i would go personally.
Future upgrades to the firmware regarding parking mode i assume might be things like if there is a G-sensor trigger the camera will revert to regular recording for a short period.
Motion detect i dont think the guys will do much with, it is fine if you park where there are not much movement in front or behind the car, but as it is now using motion detect often lead to a lot of recordings being made, and most of them will not be the motion that happen just before your car get a dent or ding.
Maybe in the future when algorithms for motion detect will be better tuned, but as it is now a leaf blowing by ( not even close to your windscreen ) can set off a recording, or a cat on a fence way out in the background. ( small things like that )
And recordings like that will just clog up a memory card or at least mean a lot of work for the camera it did not have to do as its not events relating to your car.
The G- sensor i feel are the way to go for now, and it can also be set pretty sensitive without getting too many false recordings.
I have aired ideas for other meaans of parking mode, like glass break sensor or maybe the microwave sensors some car alarms have. But this are all dreams at the moment.
The nice thing is that once you do get everything sorted out it stays that way and all you have to do is check the card regularly to be sure the cam is still recording 
