when its in the file upload, click on your pic link, then when your pictue is shown on the screen right click and copy the info on the address bar. It will look like this..
http://www.chipguide.com/tcbuploads.php?image=/chips019.jpg
highlight the area in the "Optional Image URL" box(make shure ya highlight the "http" thats already there) and right click and hit paste. It should then show. Make shure ya preview your message to make shure it worked. Hope this helps.