Mecanim window throwing errors, null exceptions in editor.

Hi, I recently installed Unity on my macbook pro and the Mecanim window is behaving very oddly, I am losing connection from Any State and errors are being throw all the time, dragging nodes, connecting, sometimes when interacting with a sub state-machine it will go back to the base layer randomly.

I tried using with Unity 4.5.0 and 4.5.3 and in both the errors are throw.

Edit: I'm on Mavericks 10.9.4