it's a bug within the "image plane" under "texture" go to "model opacity", change the input to anything but 100,then set it back to 100. It will fix the issue:>
See that cyan in the bottom right? That's 100% Blue + 100% Green. Might want to check the attitude at the door, especially when there's people attempting to help.
Valandar, just remember that adding more lights that only cast light won't add too much to render times. Its the shadow casting lights (especially omni lights) that will start to really lengthen render times. Some "basic" lighting set ups in order to get a natural feel, look like chaotic messes. Just try and put some…