Edit: Hey, you kinda got it!
I'll post it here, for the people to lazy to click the link.
![](http://www.aleromod.com/forums/attachment.php?attachmentid=10253&d=1305770633)
you have to "go advanced" then "add attachments" to add images from your computer.
if its from a different website, you click the yellow picture that looks like a mountain and a sun, and paste the direct image link into that blank.