Drag karlson.mac.app to desktop and right click it and press "show package contents" and then press contents then press MacOS then open terminal by going to utilities then write this down chmod +x then go back to MacOS and drag karlson to terminal and press enter. and make sure to put a space between the chmod +x and file And when your done the karlson file will change then go open karlson by right clicking and pressing open then an error will show then open it again using right click then open