Guys thanks for the feedback.
Since I got the regulator and associated connector last week, i haven't had a chance to fully assemble everything, hence all the components have only been screwed up finger tight.
Before doing some work this afternoon I took the time to tighten everything up. This has seen the unrestricted airflow at around 25-30 PSI, with the bleed hole taped up.
So far the compressor appears to be fine with this set, and the pressure bleeds off automatically after each burst of spraying.
Once again thanks for the advice.
Karl