[mitcheinfo]

Pues al final un enhacent a la PBO en el metodo INIT_CONTROL
if dynpro = '1321'.
LOOP AT SCREEN.
IF screen-name = 'MEPO1321-MFRPN'.
screen-input = '1'.
screen-output = '1'.
screen-invisible = '0'.
MODIFY SCREEN.
ENDIF.
ENDLOOP.
endif.