Dave, you'd be more likely to get an answer by posting a new thread so people knew what the question was.
" rigging a downhaul " Bottom line, you tie a light halyard line to the head of the sail, right where the halyard is attached. Long enough so it reaches the deck when the sail is raised. Then, you either go forward to pull it down, or you rig it aft as convenient.
First time I solo'd a J/24 I wanted a downhaul on the 150, so I rigged a light line to the stem fitting for the genoa cunningham, then turned it aft as if it was the gennoa cunningham. No problem pulling the a sail down in heavy wind.
But unless there's something really wrong, or you just don't want to abandon the helm and go forward (which is why I rigged it, J/24's don't self-steer very nicely) you should be able to place one palm on each side of the sail, squeeze your hands together, and haul a sail down while you are head to wind--unless it is VERY stuck. In which case you still might have to go aloft to clear the sail track, simply heaving on a downhaul could just jam it (a stuck rivet, etc.) or tear something.