Sorry we took so long to answer your post. The component does not have an awareness of which user it is being displayed for, as something like this can only be implemented on the application level. What you need to do is modify the code that shows the alerts to check the user against the list of the users that should see it, and only show it for those users.

Example:
if ( string.Equals(SystemInformation.UserName, "kartik777", StringComparison.InvariantCultureIgnoreCase) )
{
    UltraDesktopAlertShowWindowInfo showWindowInfo = new UltraDesktopAlertShowWindowInfo( "caption", "text" );
    this.ultraDesktopAlert1.Show( showWindowInfo );
}