Issue persists is 0.14.1.
I'm having problems with the XBox 360 wired USB controller as well. For me, the triggers don't do anything at all. There's no response in game with default button mappings, and they aren't recognized when attempting to re-map (selecting the currently assigned button for an action "highlites" it, but then pulling either trigger has no effect, as if I'm not interacting at all).
I'm on an Asus TF300T tablet (with dock). MCPE v0.14.0. I downloaded a gamepad testing app, and the triggers were recognized (and functional).
Issue persists in* 0.14.1.