I'm building for an Oculus 1.1, and using a 2015 Macbook Pro (El Capitan). I know, less than ideal.
I have successfully gotten Unity (5.4.0) and my Leap (2016) working using the Leap Asset Package (2.3.1) (future readers: unzip it in the terminal!)
But it works!
I was hoping to mount my Leap to my Oculus, but none of the OVR assets work, when I put them in my project they crash Unity. I tried the test scenes too, but every single one of the Leap Motion + OVR & OVR test scenes crash Unity.