Vincent]Login to Admin CP, go to Styles > Modify > Defualt > phpinclude at the top.
Add this into it:
PHP Code:
if ($bbuserinfo['usergroupid'] == 1) {
$regcpbutton = "<img src=\"images/top_register.gif\" alt=\"Registeration is free! Join now!\" border=\"0\">;
} else {
$regcpbutton = "<img src=\\"images/top_profile.gif\" alt=\"Manage your forum preferences!\" border=\"0\">;
Then go to Templates > Modify > Template Set > header
Find the register button and remove it, next find the user cp button and replace it with:
$regcpbutton