Doesn't Start Up

[Ikey]

Hello. I just downloaded Heli X onto my mid 2011 iMac running OS X Marverics and every time i double click on the download to start up the simulator, nothing happens. I tried downloading it a seconds time and that seemed like it was gonna work for a second but then the loading icon disappeared. All further attempts in launching the sim resulted in nothing happening. Please help

[Ikey]

Anybody?????? Please help

[cal_gecko]

I can't get it to install on my Macbook Pro running Yosemite