I've tried to reproduce the error and no success, Pixels appears to work fine. Make sure "introbtn1" *IS* the name of your image (try accessing the same image using Images1[MyImageIndex]) and also check if the pixel you are trying to access is within images boundaries. If the image you are accessing doesn't have name "introbtn1" - it'll be "nil". In case you already checked all this, then a sample code would help. Finally, does the same thing happen in Software Renderer?