At the end of the first scenario for Rapid Transit you arrive at Leipzig-Messe and then you're directed to move into the Head Shunt. The signal in front of me was red but when I checked it on the map it was marked as green. I didn't notice any call-on signals anywhere and I'm not sure if they're used in Germany. Unsure of what to do I proceeded slowly and held down the PZB override button. Now maybe I didn't hold it down long enough but the brakes activated anyway. What was I supposed to do there?