You will need to install the latest version of Web AppBuilder - Developer Edition to your computer prior to installing the custom widget. For instructions on how to install please click here https://developers.arcgis.com/web-appbuilder/guide/getstarted.htm
You will also need to have an Oriented Imagery Catalog available on your ArcGIS Online Content page. For easy creation of Oriented Imagery Catalogs, we offer our OIC-Wizard app.
Copy and paste the ‘Multi-OICViewer3D’ folder in the following location: <your computer directory>\ArcGISWebAppBuilder\client\stemapp3d\widgets
When you are working on your app, you will see the Multi OIC Viewer Widget in the widget panel
