FFS just install "rootsh" from Extra-Devel and you'll get

sudo gainroot

also you can just type:

root

But in your case I think because of the battery icon is being used by another application.
To do this is to remove the previous version:

type:
cd /usr/share/icons/hicolor/scalable/hildon/



Alternatively if you are not a Linux sage. Then you can always do this way. Easier to manage way.

Install SSH server, then Install SSH Client from Extra-Devel

Give it a password and remember it. Login should be "root" and your password.

Now on the PC download Winscp427 from google.