Research appreciated and I agree if no BMW's in the world have the Remote Park Assist yet, then coding isn't going to make it happen. I don't agree with your text in bold though:
Before the garage parker can go into production, however, it will first be necessary to clarify the legal situation regarding autonomous vehicle operation. In many countries it is illegal to start the engine from outside the vehicle or to move the vehicle if the driver is not sitting at the wheel.
I don't think that anybody doing coding is worried about whether disabling warnings or enabling the sunroof to close with the FOB is legal in a particular country, or why features are disabled in US models.
Also, states have started legislating this - The Nevada Legislature passed a law in June 2011 to authorize the use of autonomous cars. Nevada became the first jurisdiction in the world where autonomous vehicles might be legally operated on public roads. The bill was signed into law by Nevada's Governor on June 16, 2011. According to the law, the Nevada Department of Motor Vehicles (NDMV) is responsible for setting safety and performance standards and the agency is responsible for designating areas where autonomous cars may be tested. The law went into effect on March 1, 2012. This legislation was supported by Google in an effort to legally conduct further testing of its Google driverless car. As of 2012, Florida, Hawaii, Oklahoma, and California are also considering the legalization of autonomous cars.
http://en.wikipedia.org/wiki/Autonomous_car