Change 'Logged on as' message
The "Logged on as" message can be changed in the List page: Before display event. Here is how you can display user full name instead of username:
Note: Change the values listed in red to match your specific needs.
$rs = CustomQuery("select FIRST_NAME, LAST_NAME from LoginTableName where UserName='".$_SESSION["UserID"]."'");
$data = db_fetch_array($rs);
$xt->assign("username",$data["FIRST_NAME"]." ".$data["LAST_NAME"]);