I sent him a text. Hopefully he will chime in. I tried the search engine and did not get any of his posts. I do know he posted in multiple forums. You might find more information elsewhere.
Probably the simplest way I can explain what I liked for screw tightness to set them tight enough to keep the sled from moving when you point the gun upwards, but loose enough that when holding the gun vertically that tapping the butt of the gun on the ground would dislodge the sled and allow it to slide.
Set these screws too tight and you lose the benefit of the sled and too loose and you'll lose accuracy as things wobble around.