did you put it in game.txt with this code: ms0:/seplugins/nitePR.prx

The prx has to go in your seplugins folder and you have to make a new folder in your seplugins folder called nitePR (this is where you will put your game codes such as Socom FTB2 which would be called UCUS-98645)

There should be a readme.txt file when you open it up in winrar which will lead you to a link that shows instillation directions, if you didnt go to that already, it could be of use.