Hello there!
Me and my friends (we're about 5-6) are japanese N2+ french speakers planning to fan translate a visual novel. The problem is that we aren't too skilled in this "hacking" process.
From reading your posts, it looks like we have xp3 files to deal with (we are thinking of fan translating 月影のシミュラクル, I have both steam version http://www.mediafire.com/folder/3e3sdh6je0g5j/tsukikage, and DMM version if needed)
The problem is that, I tried to follow your guide,