I installed Nemo from the Ubuntu 13.10 Saucy repositories, and replaced Nautilus with it as shown here:
$ xdg-mime default nemo.desktop inode/directory application/x-gnome-saved-search
$ gsettings set org.gnome.desktop.background show-desktop-icons false
$ gsettings set org.nemo.desktop show-desktop-icons true
Now, when I start Nemo from the Unity Launcher, it places its window below other windows on the screen. I want Nemo to start like Nautilus did, and every other application, in the foreground.