.reality file not found

Using Xcode 11b on Mojave, running on iPhone 7 with iOS 13b.


Hi, I imported a simple single scene .rcproject file into an xcode project. And using the template AR project code to run it:

        let thing = try! Earth.loadScene1()    
        thing.scene.anchors.append(thing)


However I'm getting error:

Thread 1: Fatal error: 'try!' expression unexpectedly raised an error: TestARApp.Thing.LoadRealityFileError.fileNotFound("Thing.reality")


The unmodified AR template code runs fine showing the cube, am I importing the .rcproject file incorrectly?