Credit to this XDA member by name Ashomitsu that managed to build the CM theme inspired by the developers preview.
But before then Lets talk about how to install android N-Developers preview on Nexus Phons
How to install Android N Developers Preview on Nexus Phones
We’re yet to fully anticipate the Android 7.0 N android operating system which is set for launch on September 206. However, the Android N developers preview version is now available and can be installed on Nexus devices.