LayOut 2015 is supported on OS X 10.10 (Yosemite). The best is to continue using SketchUp on your OS X 10.10 system until it is updated for the final stable release of OS X 10.11.
In case you upgraded your production system, the best way to become productive again might be to downgrade to 10.10. Remember, beta software is meant for developers and advanced users, who deploy the beta software on a secondary (testing) system, not on their main production system.