The simplest step here to take advantage of electronic boost control, would be to set the boost control mode to ‘Manual Duty’ and the ‘PWM Manual Duty’ field to the duty required (e.g 60% in this engine/config example for 1 Bar) to attain the boost you would like. 


You could go as far to install a switch in-line to the boost control solenoid - when this switch is closed, the valve runs at 60% duty, giving the 1 Bar boost, and when the switch is open, the valve never receives a signal/opens, hence returning to actuator pressure only - a simple two mode High/Low boost control.