Just took out a yearly subscription and decided to start off with this course but my lack of knowledge has shown up after the first lesson.
Having reduced the number of GameScene.swift files down to one in the PinballTV folder, I added a print statement so I could check that the GameScene was being called when running on TV/Phone/Pad.
What I have discovered is that my print line only appears when running on the TV simulator. I have cleared out my project twice and am fairly sure that I have copied your coding correctly. Any suggestions as to where I am going wrong as clearly this will mean that further lessons will not work.