I have just upgraded from TC12 to 15, I am having a problem with the materials that I have created using the materials editor.

When I intorduce a new material and set the drawing to quality render it renders it in black. Yet when I use the mouse roller to zoom in or out it flashes in the colour it should be then goes back to black.

Is there a problem with the resolution of my images do you think? Or does anyone else have any ideas as to what could be causing it?