When installing E4 manager on your Mac, OS X may prevent the installer to run because it does not recognize in the proper way the installer's signature.
To enable the installer to run, go to System Preferences -> Security and Privacy. You will see below window:
Click the "Open Anyway" button in order to let the installer start.
Follow the instructions of the installer and complete the process.
Once done login with your E4 connect credentials in the E4 manager.