Wow. Have you finally made it home or are you doing all that on the road? I hadn’t even thought about trying to bleed the fuel system with a HPFP in line. I wonder if ISTA has a procedure / “special BMW tool” for that. Will the electric low pressure pump not pass pressure past the HPFP to let you bleed it?

I have started a Benz M272 engine with an un-bled fuel line after a head replacement.
It was pretty herky jerky for about 15 seconds then smoothed out fine, and has had no long term problems.