Yeah, I can see it just fine, too.
Make sure you don't have the main URL of the banner blocked in your HOSTS file on your computer, Eyre.
Also, if you've made any changes to your website's .htaccess files or your index page settings through cPanel, you might want to double-check those.
From what you've described, it sounds like there's an incorrect setting in one of those files.
And I thought of something else: Have you got hotlinking protection (in your cPanel) turned on? And when you're looking at your main.html page, are you looking at it from your computer's hard drive, as opposed to actually loading up the HTML page from your illidrithin.frihost.net webspace?
If you're trying to look at your main.html page from your computer's hard drive, whatever URL you have in your HTML code must match the folder layout in your computer, or you'll wind up with a broken image.
example. - <img src="images/main.jpg"> is not the same as <img src="main.jpg">
Hope you can figure this one out, Eyre!
Works fine on mine... idk...