Ok I'll give that a try. So the banjo bolt fitting ur talking about is that tall one beside the fuel rail pressure sensor? I also got genuine Bosch injectors from a reliable fuel injection shop. But the PRV shouldn't be popping during start up, I could see it popping during driving or wot. Doesn't make sense. It's like the fuel is bleeding back to the tank and then it can't suck it back up. But there is lift pump pressure if u crack a line and leave the key on. (at the pump inlet).

Yes, tall one by the fuel pressure sensor. If it is leaking even a littl bit the rail won't build pressure on a cold crank because the 200 rpms crankng speed is not enough to overcome the cold fuel. You have to make sure the starter is spinning fast enough also or it will hard start cold.

If you have fuel at the CP-3 inlet that is all that is needed given the rest of the system is in good shape. You might try unplugging the FCA when it won't start and see if that makes a difference. That will throw full fuel into the high pressure circuit and build rail pressure faster. They stick with age and can cause a no start.

The CR system self bleeds every time it goes into crank mode. Injectors 1 and 6 fire to bleed an air out the rail and the COV will prioritize fuel to the rail until the gera rotor pump builds enough pressure to open the return and lube ports. The system bleeds down to no pressure almost as soon as the engine is off as the injectors have cooling passages that bleed of pressure. Its these passages that generally cause hard\no start issues becuase rail pressure will not get above 3k psi on cranking and the ECU will not fire the injectors until it does.

I assume you check the cross over tubes very well for an abrasions on the injector end, cleaned them up good with scotch brite pad, made sure the edge filters were clean, and TQ'ed them correctly and to 41 ft lbs. If you skip any steps in the injector install sequence and not be very conscientious with the previous items it will come back to haunt you.

There is more than 1 thing that has to work right to get the engine to fire and all it takes is one little gltch in one piece and it will not start cold.