FUNC-SW in the system 2 menu will assign the switch to ABS. Personally I never use the ABS feature as it really is pointless. We can never lock the wheels anyway.
I set my ATL to 100 and do the setup on my speedo. I also setup the speedo to 100% brakes so basically it will pull endo's (geared diffs in the DEX410
) then tone down the brakes with the ATL. I only run 100 indoors with low grip, but I often find it down to 60 or 70 outdoors so the brakes aren't violent to use.
Not sure about the delay part of the brakes. The tranny is in the car and it's raining so can't look right now sorry.