This is where you configure the Google calendar you wish to sync.
Retrieve calendars: Until you click this button, you will not be able to select the exact calendar. If this is the first time you are using OGCS, it will step you through the process of authorising the application to access your calendar.
If you wish to revoke authorisation from OGCS for accessing your calendar, navigate to https://myaccount.google.com/permissions, click on
Outlook Google Calendar Sync and then
Select calendar: Once successfully authenticated, chose the calendar you wish to sync with.
This section allows users to utilise their own personal Google API quota. You will need to know the client ID and secret as provided within your Google developer console. Google Plus and Calendar APIs must be enabled for OGCS to work.