No "Hpl2 editor" tab in launcher

[Urkle]

It looks like the editor suite installer didn't install things to the correct location. Do you have any other copies of Amnesia installed anywhere? As the installer finds and installed the tools in the first it can find (as told by Mac OS X). To check if it installed correctly look in your "Library/Application Support/Steam/SteamApps/common/amnesia the dark descent" folder in your home directory.

There should be an "EditorSuite.plist" file there. If that file IS there make sure you are connected to the internet so steam pulls down updates, as there was a patch released to support loading of this file in the launcher.