Argh! Just found there is a small bug in the unlocker code. The tool crashes if it cannot find the necessary files! Sadly I cannot fix it until later this day!
If you bought my unlocker tool, and it crashes on your device, I am really sorry: a fix will be available tonight. But do note that you must have the NFS Shift Game installed on your device, and have played the game at least once before you can use my unlocker!