As noted earlier, FaceTime for iOS doesn't work in Middle Eastern countries: "Saudi Arabia, Egypt, United Arab Emirates, and Kuwait." Now that FaceTime for Mac is out, people is wondering if the same restrictions would apply on the new verison. SaudiMac notes that FaceTime for Mac doesn't allow you to select Saudi Arabia, UAE, Kuwait, or Egypt as your location. This means that FaceTime for Mac isn't really supposed to be supported for users in those nations.
But, just because you're in one of the above mentioned locations doesn't stop you, just go to the preferences then account then change location, and simply set your location as another country and you're good to go; Now, FaceTime for Mac will work.