OS X 10.8.2, XCode 4.5.2. I put a round button on my view and set it borderless and used it to simulate an LED. I set the color thus. Worked well. Code: [[buttonLED3 cell] setBackgroundColor:[NSColor redColor]]; [[buttonLED3 cell] setBackgroundColor:[NSColor greenColor]]; Then I colored the background like this: Code: NSColor *myColor = [NSColor colorWithCalibratedRed:(189/255.0f) green:(219/255.0f) blue:(201/255.0f) alpha:(1.0)]; [myColor set]; [myWindow setBackgroundColor:myColor]; Next I colored the other buttons using core animation/content filters. Somewhere along the way the LEDS quit, they show no color. I went back and removed all the window coloring and the core animation settings and did a clean. I even added another simulated LED, but still no color. Two questions. How can I debug the loss of ability to color the LEDS? Is there a conflict between any of the steps I took that would prevent me from doing all the coloring?