To add your Custom URL alerts or overlays, expand the “Produce” panel on the right side of the editor, enter the name in the text field of the “Add a URL Overlay” and then paste the URL for your alert/overlay below that to have it displayed on your stage. Remember to hit the “Save” button!
By default any added alerts and overlays will be placed above everything else, unless you’re running a video clip, and won’t be adjustable in terms of size or positioning. The URL will be displayed at the resolution of the Lightstream Studio 2 plan you're currently subscribed to (1280x720 or 1920x1080).