Gates and doors may be "AnimatedObject" to open automatically or manually. Other changes (default keys L and LCRTL+L, solely on foot) don't need to be implemented.
-default key L = Switch door state (by default disabled): disabled, player+vehicles, just vehicles, or only players
-default key LCTRL + L = Automatic/manual (manual by default) switch door open/close state
Mods are optional over XML:
To lock certain doors, use ‘lockdoor=”true or false”‘ in the AnimatedObject controls.
In the AnimatedObject controls, use ‘autoopenState=”0 or 1 or 2 or 3″‘ to modify the function 0=disabled, 1=on Vehicle+on Foot, 2=on Vehicle, and 3=on Foot.
To alter the door automatically (false) or manually (true), use ‘remoteControl=”false oder true”‘ in the AnimatedObject controls.

Thanks to HappyLooser