The fog of icloud - photos only download into un-useable and un-openable files.

I am trying to recover photos from icloud onto my macbook. I clan't figure out how to actually do it.

I am only allowed by the grace of the apple gods to downloaded my photos into a .zip file. The zip files now cannot be unzipped, opened, or in any way allow me to find, move, use or import the images into iPhoto or any useable form.

I recently bought a new apple device under pressure from my family. The Apple Store essentially made me activate this icloud without any understanding of how difficult it is to use. I just ant to re download a few thousadn images onto my computer. Anyone know how I can actually, without guesswork, get my photos back from icloud?