Kal Von Fiend Overwriting the files are actually very easy. All you gotta do is decrypt the game data, then translate it using a rpgmaker translation program (I like Translate ++) and once you have finished your translation just export your work back and overwrite the data files of the game with the ones you edited. I am uploading a already decrypted version of the game for you because I feel like helping but I don't want to translate the game myself. Once it is uploaded you can begin translating. If you have questions I will try and help.
Edit: below is a decrypted version of the game. this should get you started on your translation.
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