Unless I've missed something, I believe there's an import test that's missing from the set of procedures outlined in the first post. Folks should run a stop test to validate that their regulator is actually regulating accurately. Otherwise, when their solenoid closes, pressure could build up on the LP side (and then they'll dump their cylinder via the relief valve).
This procedure can most easily be added to step 3:
B1. Open solenoid valve.
B2. Check LP side is at desired level (e.g., 30 psi).
B3. Close solenoid valve.
B4. Wait 10-15 mins; check LP gauge hasn't increased more than 1-2 psi.
C. (carry on the rest of step 3).
I noticed that when my solenoid turns off. The next day my LP gauge has gone up about 2psi. Should I be worried about this situation?