All the files should exist in the zip or .rar files that are uploaded to itchio
What about data files, where the setting values are stored, like keybindings, as well as the place where it saves the fact that I've entered the password. Even when I delete everthing there are some information that are maintained, leading me to believe there has to be some cache of data somewhere... I checked roaming, appdata and MyGames and there are BBS files there, but deleting them doesn't reset the settings, so it has to be elsewhere.
Ahh good question. If you know anything about Unity we are using the PlayerPrefs to save settings ect which are stored in the registry files on windows. You can reference the below article to find where the keys are being stored.
SOLVED: Where is Unity’s PlayerPrefs stored on Windows? | by Spobwoode | Medium