The log (200 code) says that browser has asked for the picture and it has been succesfully delievered. What is the evidence that those images are not visible in the browser? You see nothing at all or those "missing image" icons that browsers usually show for missing images.
How do you know they are visible at all? Did you have them working in some other configuration?
Did you do "show source" in your browser to see how the HTML page does look like? It can be a problem with the HTML code.
Can you post an url to your site (if it's accessible) that shows this problem?
