You can add ShowingTime to your Google Calendar, so that anything scheduled in your ShowingTime will auto-populate your calendar. Follow these simple steps:
Open up ShowingTime (full website version, not mobile app), which you can access through the link on the homepage of Matrix. Click My Agent Setup, then Calendar Sync.
Select your preferred settings, and then click Create Calendar Sync Link. Keep this tab open.
Open up google calendar in another tab and click the dropdown by Other calendars Click Add by url. Copy and paste the link you got from ShowingTime into the box.