Set the lowest AA to aim high. Not sure but this should stop the wither getting blocked at the top.Yep, I def used your repeater trick. My setup is identical to yours as far as I can tell. I just re-built it, and it happened again first time, extra soul sand is placed and the wither gets stuck and can't drop down. Third time the entire AA aparatus has blown up because the Wither got stuck up top. I'll go back to Block Placers based on the other suggestion in this thread. I saw you had used 7 AA's Scotty, even tho I see everybody else is using 4 BP's and 3 AA's for the skulls only. I was wondering why they did that, but now I think I've found out. AAAARRRGGGGHHH.
Time for another break, it's double XP weekend for Planetside 2, so... see ya tomorrow, I'm done with blowing things up today. In this game, anyways.