I do not have the GOG version so unable to test it.

It does work for the Steam version 1.179.

Try to run the game, with Neutron activated. After reaching the main screen exit the game.

In the "AppData\LocalLow\AtomTeam\Atom\" directory there will be a file called "Player.log" place that somewhere I can see - like google drive, etc. and reply with the link.

It should give me some indication of what is wrong.

Hello, GOG 1.180 doesn't work either.

how to upload a file "Player.log" to you

Have you tried the 2.75 version I released on ModDB ? The latest 1.180 required me to make a new version for compatibility.

The player.log you just need to put somewhere I can pull it down from - google drive. drop box, whatever works for you

Yes, I have a fresh, latest version. no other mods,

https://drive.google.com/file/d/1Dc9NXJwrQYrnAQrkgIfuo15EmhQYVWFQ/view?usp=sharing

From your log:

[Manager] Injection...
[Manager] Initialize.
[Manager] Version: 0.23.4.0.
[Manager] OS: Microsoft Windows NT 10.0.19043.0 AMD64.
[Manager] Net Framework: 4.0.30319.42000.
[Manager] Unity Engine: 2019.4.281.
[Manager] Game: ATOM RPG.
[Manager] Mods path: E:\GOG Galaxy\Games\ATOM RPG Post-apocalyptic indie game\Mods.
[Manager] [Error] Assembly 'AtomGame.dll' not found.
[Manager] Injection canceled.

This indicates you have the Unity Mod Manager installed for this game. The version of 0Harmony.dll it uses is not compatible with the version Neutron uses.

You would need to uninstall the Unity Mod Manager. To be clear just uninstall it for Atom-RPG. Appears it is not installed correctly anyway.

ok i messed up something with UnityMod and had to reinstall GOG and Atom game, now it works, thanks for help