We could of couse do that but I don't think a simple way to launch a filemanager as root is the best idea. Yodude explains this prety well in the other emelfm2 as root thread. And I would *never* recommend anybody who does not already have sudo experience to mess with the sudoers file. The best option is a separate script that launches it and a desktop icon for that. Even thats pretty dangerous.

Did u run the leafpad script in a non root terminal?