Last weekend camping, I kept smelling natural gas, and I discovered a
constant, small outgassing from somewhere around the regulator (this
was with main tank valve open and the fridge on, at night when
temperatures were declining).  If I closed the main tank valve the
leak stopped.

I couldn't tell exactly where the gas was coming from, but it seemed
possibly near a seam, not near the little opening on the regulator
(which I presume is a pressure release vent?).   I assume this isn't
normal?  Or does the regulator leak as a regular function of
operation?

Since a new one is only $30, I'll probably just replace it.  Any
tricks to doing it well?