Raising and lowering sail in a chop is alway a bit fraught. There is, of course, no reason to ease the sheet to reef. Instead of being directly head to wind, I usually have the wind about 45 degrees off the bow which means the sail hangs out more to one side. When making sail, don't let the sheet off completely, just give it enough slack that you can haul up the sail without too much energy being wasted. Ease it out again at each batten, or in between, as it suits you. When you are raising the sail, you can haul in the YHP every now and then to stop the yard thrashing about. I suspect your tolerance levels for all this behaviour will increase as you get used to the rig.
In these conditions, it's sometimes worth reefing incrementally, and adjusting the sheet fairly often rather than dropping the sail all at one time, if you are intending to motor with the sail down. I would be inclined to keep up the top two or three panels all the time, in a seaway, to keep things steadier.
I don't have a boom gallows either and think it would be impossible to fit one on the extreme camber of FanShi's deck. However, I have two lengths of Dyneema fitted with small carabiners that clip to the end of the boom and the deck stanchions. These steady the sail surprisingly well and are especially appreciated in the summer with all the power boat wakes!
I love the colour of your sail, by the way!