I added some information about the color coding I have found in the games regarding the null and I would love to hear your thoughts. I find that Red is the primary color used to create portals. It is often paired with moving through time and space.
It appears AS discovers the key in the second game that the Green wavelength is needed to open specific doorways. He says specifically "With it you may lift the veil, peak behind the curtain." Green is always paired with those who see the unseen.
In the third game the craftsman sets up a Red beam to open doors and a green wavelength is needed to tune them. If you use the Green crystal from Maggy in the end with the red that comes from the Craftsman key you get the Escape ending.
Blue is tricky but it seems to be the most mysterious and powerful. If you pair only the powerful Blue crystal with the red from the Craftsman's key (without the green associated with the truth) you unleash the null on the world.
It is only when you combine all three wavelengths combining the red (manipulation of time and space), green (the ability to see the truth) and blue (raw null power) that you get the Lost ending.