Great game but...

After installing & playing this game, my iMacs screen wont sleep nor will the computer itself sleep. This only happens after playing the game. If I restart the computer & dont start the game everything works fine. No problems until I start the Grid game again. Even the PleaseSleep app wont force the computer to sleep. Grid must keep something running that wont let things sleep. I searched everything that I can & cant find what the problem. Its frustrating when you finish playing the game & your monitor stays awake all night. I dont want to have to reboot every time after playing this game.

Rotgut about GRID™