My guess is that you haven't installed becomeroot; and if you can't install anything, then you can't install becomeroot now; and if you can't install becomeroot, I don't see how you can be in root in Xterm.

If you have becomeroot installed, you just open Xterm -- look around your list of applications and you'll find it -- and type

sudo gainroot

and then click enter. Your prompt will change from $ to #. Then type what I have in Post #7 and click enter.

But if you enter "sudo gainroot" and that doesn't get you to the # prompt, then I don't know what you can do other than flash the device and start over. (Before flashing, first do a backup.)

Maybe someone else will come along and tell you how to get around the problem of not being able to do the "sudo gainroot" thing.

Good luck.