UE4 crashes on play upon adding "MyCar" blueprint into world

I am following the Vehicle tutorial and I can add the MyCar skeletal mesh into the game, but when I add the blueprint into the world, with the full bone names of the tires assigned, and try to play, or simulate, the game just crashes and I have to force it to quit. I don’t know where I am supposed to look for log files to figure out why it’s crashing. I am using UE4 4.0.2. I have a newest generation Macbook with 16GB RAM so I don’t think that my hardware being too slow is the problem. Please let me know what I can do to resolve this. Thank you.