You can do that tutorial without getting the object pallete. All an object pallete is, is a list of object (that already exist in the geck, and that you already have access to) and an easier way to group and place them in the world. The objects reffered to in that tutorial you already have in the GECK. So just go along using them, ignoring the placement directions reguarding the object pallete, and simply drag them in to place like everything else.