•Created one repository "rep_1" and shared a project "krty" with vuser name"Search".[Now revision number in repository changed as 1]
•Later I renamed the vuser “Search” as...
You did the right thing. If you would like to keep a specific version of your project you have to tag it.
There's no other option to get back to a specific revision other than...
You cannot backup the license repository but usually there's no need to do so. If you try to restore NLS files, the activated licenses won't work anyway.