What the **** do you do with the *.logonxp files ?

I have logon studio installed. But now you have to explain something to me: there are 3 pre-installed logons (each in seperate directories and all BMP-files)?Now what do these *.logonxp come into the story ? You can import files like logonui.exe and convert them. The only I thing there is possible to do with the logonxp-files is to load them, but this doesn't make them the active XP-logon screen. Please explain: I really don't get this .

GreetZzz

Tim