I've really enjoyed the demo, puzzles were nice and the graphics are gorgeous, congratulations!
Played in Linux Mint 21.3 Cinnamon, 64bits, X11, every option worked fine except the F12 fullscreen toggle, that made it crash with this message:
X Error of failed request: BadWindow (invalid Window parameter)
Major opcode of failed request: 40 (X_TranslateCoords)
Resource id in failed request: 0x2800457
Serial number of failed request: 453
Current serial number in output stream: 453
AL lib: (EE) alc_cleanup: 1 device not closed
Can't wait to play the whole game, great work! Thanks!