Finally solved all issues with CNG.

[dikidera]

No more ECM-F00D, the sensor itself was absolutely fine. The pressure sensor on the governor/evaporator/vaporizer is indeed a pressure sensor, this pressure sensor uses Pin 2 as the Vout signal, unlike Bosch sensors that use Pin 4 for this purpose.

Curiously it is a 4-pin sensor, but pin 4 is unused, I am very curious what it is, I keep thinking it's also some Vout signal for pressure as well, but who knows.

I had initially concluded it was a temp sensor based on the fact that all Bosch sensors used pin 2 as the NTC/temperature sensing, but not this.

No more ECM-4400, after changing the stepper to the "Type A" and separating the driver board in it's own little box away from the engine, the car is working fabulously.

There are a few small issues such as a leaky evaporator into my intake manifold, but I believe I have a solution which is a cheap trick before rebuilding it. And a few slight slight misfires on idle, but other than that...perfect.