The first thing I did when I set up my kegging system was to take everything apart and clean it all together. Unfortunately, what I didn't know at the time is that I had several different posts and poppets and mixed together. It took me a while to figure out which poppets went with which posts. The issue with leaking gas could be because of an improperly matched poppet that is not sealing properly.
As far as the regulator, make sure the lock nut is not interfering with normal adjustments. Usually it prevents you from raising the pressure higher than you want, not keep you from lowering it, but who knows...
perhaps a line of single hop IPA's - there's so many new hops out there!!!