Ron Martig

I’m new to war games so please bare with me here. I was playing the Riesburg scenario as German and had all my men hidden for the first turn. A Sherman appeared from the back of the battlefield about 60 or 70 meters to the right of the road, it was in open ground and not buttoned up. My sharpshooter was in the original setup location and had a clear line of sight to the Sherman, (about400m) so I unhide him and target the tank to see what will happen. He fires one shot and the tank buttons up. Now for the rest of the game the buttoned Sherman never moves one inch, I think it did fire the main gun for maybe the next 4or5 turns, that I can remember anyway. After the end of game I checked its status and one crewmember was dead. My question is which dead crewmember would affect the tank in this manner (or did it just get stuck) and has any one else had a sharpshooter kill a tank crewmember?