Firstly as a newcomer to KiCad I must say that I am really impressed with the application. As someone who has used Eagle and other PCB CAD programs for many years I believe that KiCad is something really special that has the potential to grow and grow both in scope and in following. I wish I had discovered it earlier!
For clarity I should have described the layout editor as "Pcbnew", the board layout editor. It appears that despite the other modules having options to change the background, no such feature exists at present within Pcbnew. I should make it clear that this is not just a whim on my part, it really does make a huge difference to the usability of the layout editor for users like me who through age have lost a degree of night vision. Thanks for the suggestion about changing layer colours Joan, I will do this as a work around but I suspect that despite this, the black background will still cause fatigue.
Is there a way to submit this as a future feature request?