In the route intro scenario for the LGV DLC, the loco's Master Switch is set to off despite the tutorial saying that the train is "ready to get moving." Because of this, when you move the throttle forward as prompted, the train does not move. Strangely enough, the narration will continue when you push the throttle forward with the Master Switch set to Off regardless, but the tutorial will progress no further until you properly start the loco. Here is a video of this issue in action: https://streamable.com/c6waww