how to install logon screens

I did that and I downloaded that Seraphim of Light one and it just isnt going. I don´t know what I´m doing wrong. Can someone help me?

that skin wasn´t made for the stardock logon .. clicking on the program that it´s made for (right after the title) will take you to this page .. and at the bottom you´ll find advice what to do with it .. how te replace the original systemfile for this one

You can use StyleXP to change your logon screen,And it will not mess with your system files!! :)