Blade Twisting?Follow

I was wondering if Blade Twisting stacks along with crippling poison(by stack I mean that they are both on at the same time but the stronger of the two takes effect). Also, does vile poison resist effect work on druids shapeshifting? Does the daze effect get removed as well when they shapeshift? I don't want to mess up my rating by just spec'ing combat and going in with so many things unknown(even though my rating sucks).