Hi there!
Recently I tried some Video projection style scene. Normally you would use a spotlight and apply a texture to it. As this is not possible in Corona, as far as I know, I tried different solutions.
Frist one: Light Material with 100% Directionality. This actually doesn't work very well. The resulting image is extremely blurred. You can size up the Light Material Plane to sharpen the image. But there are limits to this approach, when doing interior stuff.
Second approach: Plane with a Texture in the Refraction channel. And a light source behind it. Works like a real world projector, but the light source must be very small, to get a sharp result. This results in ridiculous light like 999999 and Exposure up to +20. That's ruining every scenes light balance.
I couldn't figure out another, practial solution. So maybe someone over here got an idea?
PS: Attached you can find a sample image. Left hand-made projector, right side plane with Light Material.