I had DUPLICATED the normal patch inside the EXTRA folder by mistake, instead putting there the additional patch. With this update that is fixed.
Now the normal patch and the optional patch inside EXTRA folder are different; the second does really replace the enemy names by the Spanish names used in modern translations of Dragon Quest series.
It has been an human mistake.
Here is a full hack for Castlevania which changes the levels and palettes of the game. Also you start with 99 lives (due to difficulty of the game) and also the axe uses no hearts when thrown.