FS17 wont start now

[jb59]

I purchased and downloaded FS17 in January for my grandson and today it stopped working. The icon he normally clicks to start the game is now subdued as well.

Do I need to re-download and re-install? As I'm new with using Apple computers and this is what I downloaded the game onto, I'm not sure how or where to find the original .exe file to do this.

Thanks for any help

Joe