With the leather pad only, it is perfect centershot. With a tooth pic behind it, it sticks out 1/4 at the length of the arrow held at centershot.I have only got 1 DAS connection bow but I've been told that you keep the thumbscrews loose until after it's strung then tighten them.
Do you have the shelf built out at all? What does the arrow alignment look like when viewed from behind?
P.S: Just keep the tiller even and increase the BH until it gets quiet.