Simply pasting the xml back will do it, why it doesnt for you I am not sure. Only thing I can think of is you are not pasting a xml of the same name or not starting the xml you have loaded. The other thing I can think of is you are placing a backup rather than a xml.
As to your other part of your question, if you go to I think Operator menu you will see a restore option, you can then choose out of the list which backup to install.
Hood