Does anyone knows how bunny black did the exe translations?

I've manage to manually find some string on the exe. But the game breaks when replacing it.
If I make any alterations at all, even in an empty byte anywhere on the file it gets corrupted when starting the game.

I'm guessing there is a checksum or something to validate the .exe signature that breaks when altering any byte. The bbtools had an exetextpatcher but I don't know how to use it and even if It'll work on other softhouse chara games apart from bb2. If it does, can someone explain how to use it?

So, does anyone know how to translate the .exe strings or how to extract and change them more effectively?