Thanks! I'll have to tweak the zombies. Another idea I had was having them respawn. And bats just fly straight, they're a very one-time enemy. I didn't get around to it, but I wanted to change them to swoop down and chase you like the flying demon things in the original game (which I haven't really played either).
You actually can exit the editor. Just open the menu (the "..." button) and there's an option to quit. Perhaps it was too dark to see it's a separate button from "Copy Code".