It is a safety related issue to stop fingers getting caught. The roof motor is powerful to move all that metal so could easily do nasty things to little fingers. There's no back-off control like you get on windows. It's all software controlled so I suspect that in some territories it is an allowed option but is disabled in the litigious countries.
To open, just keep the button on the key-fob pressed.
To open, just keep the button on the key-fob pressed.