Motor cranks won't start

Having ascertained that fuel is getting to the injectors and then to the engine intake manifold, the motor will crank and start on aerostart but won't fire when this runs out, new pump, regulator, filter, plugs and all fuses checked, I'm stumped as to what else I can do, help please before I burn the bloody thing, thanks all

Check the tip over switch is correctly oriented.

Hi, missed this been busy with life.
So it runs on aerostart - but stops when that's removed. Can you tell if injectors are actually firing fuel into the intake ?