Unable to start - fuel issues?

[viator]

Hi

Thank you for your kind concideration and reading through this rather long post:

2007 R1200RT-P

Problem:
Bike will not start or sometimes I can get it running for a minute or two, but the moment I touch the throttle, it dies.

History:
The bike started cutting out and was taken to BMW dealer. They found various faults:
1. ABS faulty (this was a know issue for years and did not stop the bike from running)
2. blocked fuel vent
3. faulty KOMBI
see attached report and wanted to replace:
1. whole fuel pump
2. whole ABS
3. new KOMBI
They want my kidney plus other organs and also my extended family's plus future rights on all kidneys of future generations, plus all of our money as well.

Work that I have done since then:
1. Replaced the ABS motor - error gone now.
2. Cleaned the "invisible" fuel filter as per this video https://youtu.be/xdyHT3pGm_A
3. I've got a GS-911 and there are no errors present. (It is a old version with not all the new functions)

Tests performed:
1. With GS-911 I tested all the injectors, idle servos and fuel pump. All works. There is no option to test fuel pressure.
BUT - I do not get fuel returning to the fuel tank while the fuel pump is running. It streams out at velocity when I push down on the one way valve on the outlet port,
but no fuel returning when I manually open the stop valve.
2. The vent that BMW says is blocked (indicated on diagram attached) is open - they talk rubbish!
3. I do have a very short log run saved from the GS-911 until the bike died that I'll attach as well.

Questions:
1. Am I correct to assume that there must be fuel returning when the fuel pump is running, but the engine is not running?
2. Are there any parts in the attached diagram that I've marked that could be the problem? What is item # 2?

Again, thanks for any help.

[David.]

What is item #2.

Fuel Pressure Regulator