Staff marks work just fine, but wells and dagger offhand Enfeebling Blood and all well skills are cast behind the player if you don’t mouse target ( if you just click the skill on the bar with your mouse ). This causes the player to turn around and stop attacking.
I think the casting center is slightly behind the center of the skill. It started happening this update (October 1, 2013). This happens occasionally with updates but is usually corrected in following updates. Hoping they’ll see it this time too