This is the most updated version, download this one. The hand skin in the mod is made by Smasher006. And used with permission.
Portal Map Editor (or "po_editor") is an modification to the game Portal 2, it's sole purpose is to build maps in a simple and effective fashion. It's not supposed to be the best choice of Portal 2's mapping tools, but rather as an extra asset to the primary mapping tool which is of course, the Hammer Editor.
It's features are limited, but you can try out the basics of the Hammer Editor and see how it turns out without having to use extra effort.
I advise you to not post maps created by this editor, as results would be limited maps and you cannot save maps created in this map editor, in map format.