These blocks can act as three kinds of blocks. Regular blocks like wood, barriers like team barriers, and ghosts like posters.
You can choose for it to act like a wood, barrier, or ghost block by simply tapping on the middle of it in creative mode. The middle will have a letter (or symbol) to represent each.
Just like dirt, stone, or cobble terrain blocks, painting it a non emissive color does nothing except change the way it shows up in creative.
Painting it and emissive paint would work like a light block from Minecraft.
The blocks would show up as a diagonally transparent striped block.
This would be incredibly helpful to builders allowing them to make their maps more immersive! I feel the building community would absolutely love this block!