Hmm . It was a weapon trap and should have automatically reset, so that wasn't the problem. I'll test something with a pressure plate next, but it's not looking good so far. I'll also gen a new world with adv traps already set to yes to see if it makes a difference.
Edit: I'm having about as much luck as Qloos. Pressure plates are a no go. I've yet to try it with a new world yet, but I'll get there.
Double EDIT: I'm sad to report that even genning a new world with adv traps on yes, pressure plates and weapon traps do not work.
We still have levers however, so traps will have to be guess the right lever.