okay, i want to change my comics thumbnail but ... how?

in comic overview i can see the current file but there only a 'send' button. i dont wish to resend the already used GFX and i'm baboozled on how i replace it. i submitted the image up via the file manager but now i'm at a loss on how i apply it to the thumbnail :S

You can't do it from the file manager, that's the place for things like custom navigation buttons and extra html pages. Understandable mistake though!

You're missing the 'browse' button next to the blank area. Usually it will show up in a different browser, or if you're using IE8, you can turn on compatibility mode. :] It's just coding that comes across inconsistently between browsers, unfortunately.