The fifth drawing is unusual, in that it combines with the eleventh drawing to form one larger picture. If we’re meant to see a sequence, or narrative (as the numbering implies), then this may be a scene that we return to later. Or, perhaps, the right side is the focus now, and the left side later.
We’re inside something, indicated by a rough semicircle, and an even sketchier line at the back. There’s also a ladder leading out of it, with seven rungs (if number is part of the meaning here). It could be the inside of a UFO, which would make this picture the only one with an explicit reference to UFO culture. However, it could also be a dome, arch, or cave. If we want to continue the Mesopotamian interpretation (which is tastier with at least a grain of salt), I can point out that the Sumerians saw the universe as a closed dome — as did, of course, the authors of Genesis, among others.
We have four beings here. Unless my apophenia is acting up inappropriately, I recognize the couple on the right as the first and fourth creatures from the third drawing. One seems to be female (breasts, skirt, heels), and may have a baby on her back. She also has curious pronged antennae (and different ones from the figure in the third drawing). The creature next to her looks more like an anthropomorphized animal (a bear, maybe?) than a human, and is handling luggage; it may be male, and I read him as the husband. The couple on the left don’t look like any of the beings we’ve seen before. Since we’ve been told that the pictures came from “contactees,” it’s easy to see these two beings as aliens; or, at any rate, as the ones doing the contacting. If so, they’re contacting a family.