Mandatory Profile help

[XI AlphaMale IX]

At work, I assembled a lab at one our client's offices and the boss wanted the users to see the same thing everytime they log on. I recommended mandatory profiles, but when I changed ntuser.dat to ntuser.man, the profile reverted back to before I'd done ANYTHING to it (only icon on desktop was RB in upper left corner and wallpaper was gone). I want it to revert back to the way I set it, not back to "nothing".

The machines are XP SP2 (for now) and the lab is on a Workgroup. Can anyone help? If you need more info, please let me know. Thanks in advance.