TourBuilder allows you the ability to control your thumbnails in the Google Maps carousel you see on the left side once you publish your tour. This feature is only available in island mode. It is not an option for tours using levels.
To control your thumbnails using island mode:
1. Navigate to the Build tour step of your tour in TourBuilder.
2. On the left side below your constellation map, you'll see your connected scenes. You can select which scenes you wish to appear in the carousel by selecting the respective checkbox. If you've unchecked the scene, it will not appear in the carousel.
In the example below, all scenes would be published to the carousel.
Important: never uncheck all of your scenes. At least one scene must always be checked, or your tour will not publish.