In the game Cube Escape: the Cave, you can finish the second part by merely collecting the cubes.
You, however, can also go to locations marked on the map (hotel, church, cabin), and find instructions of secret coordinates, that guide you in the end to find the secret box with Dale's Birthday needed as a key code.
While navigating the lake, I came across many other things, such as the soul of Mr Deer in many a location, and a rock with 4 symbols, that was seen again in Paradise.
So can anyone share coordinates of such special findings?