We have tried importing Global Viewer extension using https://developer.thingworx.com/resources/guides/create-global-plant-view , but how I can customize this application to add our plant in it?
You can add tile to console so that you can access it in Manufacturing Apps Console page.
Try duplicating the plant coming from extension to your plant which you want to display .
There are no documents as such for this scenario . The way to duplicate this via Thingworx Composer using the duplicate option .