Please note: This only applies to Micro Snitch versions downloaded from our website. If you bought Micro Snitch in the App Store, the Mac App Store handles the registration for you.
To register Micro Snitch, click on the Micro Snitch icon in the menu bar. From the menu choose “Open Micro Snitch Preferences”. In the left sidebar click the “License” button to open the registration sheet. Copy and paste the key into the “License Key” field and click “Register” to finish.