Forgot to mention that this vehicle has an electric lift pump which appears to be priming OK.

Its pretty obvious from the test of opening the fuel rail pipe to an injector and cranking the engine that the fuel pump is dead as no pressure or flow is present but why does the pressure sensor behave as though the pump is doing its job even with the pipe to the injector left open?

Its not imagined reading both Pico and Launch were showing side by side results of correct cranking pressure.The fuel rail only has the fuel pressure sensor fitted and the pump has a regulator solenoid which again was shown to be pulsed by the ECU during cranking.