DEAR22 Threads Print Orientation/Layer Height

Just curious, what print orientation and layer height are you guys using for the DEAR22 threads? I printed some test pieces according to the readme (which is a bit sparse) which suggests vertical print orientation with tree supports. I tried without supports as well. Both prints of the upper threads looked ok, but the barrel nut threads just kept falling apart, even with supports. I am using .6 nozzle/.3 layers, just bambu default pa6-cf profile but I have it slowed down some. I've been getting accurate dimensions with these settings, not so much with lower layer heights though. I really hate printed threads...