I have an older Mac that is restricted by Apple from installing Mac OSX more recent than 10.6.8 Snow Leopard. When I attempt to launch KSP 1.1 using either the launcher or KSP app, the Kerbal icon bounces once or twice in the dock and then disappears, and nothing further happens. This is probably an issue with Unity 5, and thus there is nothing that can be done. The minimum system requirements listed on the website call for Mac OSX 10.6 or greater. If this issue is unsolvable, that line will have to be revised.
When I attempt to run the launcher, this turns up in the Console app:
4/20/16 11:34:49 AM com.apple.launchd.peruser.501[106] ([0x0-0x28028].unity.Squad.Kerbal Space Program[268]) Exited with exit code: 1