Re the problem. I didn't want anyone to see any user detail as in user name.
I have hacked [/htsrsv/message_send.php]
From

	{	{	// If EMAIL has been sent:
		$Messages->add( sprintf( T_('You have successfully sent an email to %s.'),
			( empty( $recipient_User ) ? $recipient_name : $recipient_User->get_username() ) ), 'success' );
	}
	}

	{	{    // If EMAIL has been sent:
		/* $Messages->add( sprintf( T_('You have successfully sent an email to %s.'),
		( empty( $recipient_User ) ? $recipient_name : $recipient_User->get_username() ) ), 'success' );*/
		$Messages->add( T_('You have successfully sent an email to the Site Manager.'), 'success' );
	}

I could probably do more like: [get_usernick()] or something