Hi Paulo, also when you are in the Image command manipulating an image there are snaps that are active at that time on the corners, edge midpoints, and center of images to snap other images onto those spots.
Check out some of these posts for some demos of how to snap images together in a few different ways:
Or like Martin mentions above you may want to set up some geometry first that is aligned how you need it and then snap the images onto that when you add them.
