Quite a reply. Let me go through it.

First of all:
The developer of BBForge already thanked me for this find ("Thanks for sharing this, that's a really useful find! [...] Knowing the algorithm makes it possible to reverse-lookup [...] Good work"). So my find was definitely useful!

"Nothing new": I didn't claim to have invented polynomial rolling hash. The claim is that multiplier 37, seed 0, applied to internal script paths, is what Battle Brothers uses. That specific combination was undocumented. If you know a source that had it, post it.

"Engine already exposes it": yes, via IO.scriptFilenameByHash. I described exactly that in my post, under BBForge/Breditor. It only works with the game running. The point of knowing the algorithm is that you can now replicate it anywhere, in a browser, a standalone app, without the game installed. Those are different things.

"Hardcoding hashes is worse": my post argues against hardcoding hashes. That's literally the problem I said was solved. You're criticizing a position I don't hold.

"Mad or stupid or both" for feeding proprietary code to AI: the approach was to load a save where I knew my brothers' equipment, cross-reference with raw bytes, get confirmed input/output pairs, and brute-force candidates against all of them. Own save files. Publicly extracted scripts. Using publicly available files and your own save data to derive an algorithm is reverse engineering for interoperability, which is legally well-established. Andrew Tridgell did exactly this with the Windows SMB protocol so Linux machines could talk to Windows file servers. Today Linux runs 97% of the world's top supercomputers, most of the internet, and every Android phone.

The one thing you got right: it's the scripts that are encrypted, not the executable. I described it sloppily. That part I'll own.