Activating Urban Turtle requires registering your vendor-provided license. This file will be sent to you by email upon signing up for a trial or once your license purchase or renewal are processed. This precedure is the same for Urban Turtle for TFS 2012 and Urban Turtle for TFS 2013.
Note that registering a license renewal is done following the same procedure.
To register your Urban Turtle license, open the Urban Turtle application within the Team Foundation Server WebAccess page.
Once in Urban Turtle click on the "about" link (1) to display your currently registered license information.
Click on "choose file" to select the license file to register (2).
Click on the "Apply" and you should see a sucessful registration screen like the following: