Hello everyone,
As noticed by @supersmo, a bug was present in the game preventing you from finishing it, it is now fixed!

If you want more details about it and how it passed my vigilance, it is an issue in Godot due to a filename going from "glassWall" to "GlassWall". Some files, including the first one in "The Darkness" level, were still referencing the old one.

If the editor seems to not be case-sensitive on loading a file, it is now clear that the Windows build was.

Hoping you'll enjoy the second part of the adventure (it was blocking 40% of the content...)

Le DoubleSept