"However, the C-1 uses a drive-by-wire system. That allows it to have the familiar, intuitive interface of a car, while using two-wheeled turning dynamics. This is where the gyro technology gets really interesting: the C-1 takes information from a wide array of sensors to determine everything that’s going on around it, from road surface conditions to wind to traffic. The vehicle is then able to take input from the driver – from the steering wheel and accelerator/brake pedals – and translate that into both movement of the front wheel and a precise lean angle to complete the desired turn."
It doesn't actually say it, but this implies a substantial amount of the turn is accomplished by loading the gyroes (there seem to be two under the floor) and a little bit of front wheel turn.
The other question I had is answered by the fact the motors are in the hubs, so there's no space in the cabin lost to motors.
