Really liked the concept and the sense of urgency you get with all those numbers increasing as time goes on... The look and feel is also attractive, and appropriate for the theme. Maybe as a next step some animations could be added to make more clear what is going on in real time (e.g. rockets saving people). Congratulations on your first game, keep up the good work!
As a heads-up, I had to do "chmod +x GameOffProject-MassExtinction.app/Contents/MacOS/GameOffProject-Mac-Shipping" before launching the .app to make it work.