Okay, so I've found some solution to untranslated segments. It's not perfect, but it's better:
1. Download
broken_division's patched game and
AkagiVoid's patch.
2. Extract broken_division's zip into a folder (I'm going to arbitrarily name it the "game" folder). You should now have a folder called "RJ391974-Ver1.27" inside your "game" folder.
3. Extract AkagiVoid's patch into the "game" folder. You should now have a folder called "RJ391974-Ver1.27" inside your "game" folder, alongside a "js" folder, a "data" folder, and a "translation.trans" file (or "translation", if you have translator++ installed).
4. Move
ONLY THE "js"
FOLDER INTO THE "www"
FOLDER INSIDE "RJ391974-Ver1.27". This should solve issues involving the menu not being fully translated.
5. Play game.
The MTL is readable, if not the best. But as somebody who gets tired manually editing a 450 MB game, I don't blame broken_division for not wanting to manually edit the translations of around 6000 lines of code themselves.
As for the active messages, I've just realized that they need to be translated, and so I'm doing that right now. As with AkagiVoid, I'm too lazy to proofread too carefully, but maybe I'll post the translation later, if somebody tells me how to do so (I don't imagine it's too difficult to figure out, but again, I'm too lazy to learn).
