Driver mode controls: Press 'D' key to accelerate, 'A' to decelerate. Key "H" - emergency brake; "K" - open/close doors. (!) You should stop at the stations by the blue marker which appears at the bottom of the screen once you entered the station. Audio announcements are automatic. Passenger mode: No controls. "P" - debug mode.
This is a beta! There could be some bugs, graphic issues or whatever. To be fixed in next versions.