I might be missing something, but I'm not sure how to use this. I can enter the editor, but I can't seem to figure out how to make or put down persistent blueprints? Am I missing something? I love the idea of this mod.

You have to craft a persistant blueprint and place it in the editor in one of the squares and build something around it. Then when you click on the persistant blueprint you get teleported back out of the editor and should have a persistant blueprint in your hand. Place that and everything from the editor appears as ghosts.