That is the problem I am having, the red regulator is leaking gas through the vent hole. My trailer has a rubber hose running from the driver side to the two stage auto switching regulator. If I just attached the driver side pigtail to the rubber hose, I would have 2 less connections. By the way, I read the UL label on the 12' hose and it is rated for 360 Psi, so it seems to me that the red regulator on the driver side tank is superfluous, and just something else to go wrong. If I were worried about the 12' hose breaking, the pigtail already has a blowout protection valve in it. I'll continue to research, but right now my inclination is just to take the regulator out, and hook the pigtail directly to the 12' line that goes over to the auto switching regulator.
As far as I can tell, all the regulators carried by grill stores are low pressure regulators and are not suited for this application.
2010 Rockwood 8280WS Fifth Wheel
2013 F350 Crew Cab SRW, Standard Bed PS Diesel
Reese Airborne Pin Box, Reese 16K Manual Slider
Camped 28 Days in 2012, 23 Days in 2013, 29 Days in 2014, 30 Days in 2015, 9 Days in 2016