EasyAR implements SLAM on Android and iOS devices with special optimizations, it is not recommended to run SLAM on Windows or Mac. The algorithm effects will be totally different. SLAM for Windows and Mac is only for development purpose, to ease content creation.
The ARScene prefab is an empty object with a ARSceneBaseBehaviour.
You can set a few values that can be used by the ARSceneBaseBehaviour.
See ARSceneBaseBehaviour for more details.