The control and drive of the system is affected by the Omegas Electronic Control Unit (ECU) which is therefore considered the "brains" of the system.
It takes a trigger signal from the Petrol ECU and diverts this signal to the gas injectors via a series of calculations (in order to deliver the correct amount of gas).
It relies on a series of inputs from the engine for these calculations. (Water Temperature, Gas Temperature, Gas Pressure, engine RPM and many others).