Co-op championship glitchy!!
Spent the last couple of nights on co op career to get achievements and the constructors one worked fine but for the drivers championship we had the same number of points so we were joint first and neither of us got the achievement!! Very annoyed so it looks like there must be an out right winner so will need 2 playthroughs and for us 3.. Grrhh.
Another way we are going to try is--player one comes first each time and player 2 hold everyone else up and staying out of the points so player one can build up a good lead and hopefully the achievement will pop up mid season to save doing all 20 races