Nothing wrong with the image, it’s a PNG file. You can just drag that on to the Dashboard and it will open up as an engrave.
Measure the thickness of the MacBook Pro that you are trying to engrave with a good pair of digital calipers. If it is over 0.50 inches thick, you will need to remove the tray, prop the surface of the Macbook so that it falls into the correct range, and do some calculations so that you can set the correct thickness for it in the Unknown Materials column. I’m pretty sure the laser isn’t going to fire if the laptop is too thick.
(Link to the height calculator if you need it: here)