Single Player Scenario won't start

Clicking "Play" does nothing in the single player scenario for 1.4c Altis... I'm guessing the problem is between the screen and the chair, but I'm not sure what I did wrong.  All I did was download the 1.4c altis folder from Github, and threw it in my scenarios folder in the steam folder..

A3W doesn't work in singleplayer. If you wanna play alone, you must place the mission in MPScenarios and host a LAN lobby in Multiplayer.