check this out:
This is what happens when I try to use the new mask feature in Adobe Premiere CC2014: it's off set halfway across the screen. I did a very dramatic curves adjustment just to illustrate the problem better. I tried both the circle and the square mask, different effects, and even closing down and reopening Premiere. No luck, same result every time. I even tried just moving the mask far to the left to compensate, and when it hits the corner of the screen it starts to cut off the mask. Ok, I'm now officially waiting for the CC2014 update to start using it again. Much to buggy.