With each step where getting closer no?
Since you're using Chrome as a browser you can right click one of the 'broken image' icons and click 'inspect element
'. This will show you the rendered source of the html and might give a clue as to why the images aren't showing. (see screenshot 1)
Next to that you can click the 'resource tab
' and reload the page. If you scroll up/down you'll see all individual files being loaded (or not). The ones Chrome couldn't load will show up in red and have a status of 404.
(see screenshot 2)
When you hover over the name of that file, a tooltip will show you the exact URL it tried to load it from.
To take a guess, I'd say you try and return the image with a 'hardcoded' full url like (http://localhost/image01.png) but you're browsing the website to Sitefinity's projectmanager which operates not on port 80 but (in your screenshot 60876). If you let your .ashx return the images with a relative path (/image01.png) it should work better.
But this is just a guess based on the previous postings.