I think the guy sounds genuine enough. He has explained his position, on which he's actually right, there isn't anything specific in the rules about using programmes.
He's also said from now on he'll inform his opponent that he may use a programme. What more can you ask? He's been very open and upfront in my opinion. Give him a break!
(ocultar) Si deseas jugar una partida contra un adversario de nivel similar, puedes definir en tu invitación de nueva partida un rango BKR apropiado a tu interés. En tal caso, nadie con un BKR fuera de dicho rango podrá ver o aceptar la invitación. (Katechka) (mostrar todos los consejos)