Okay...right click on the image, choose "Properties" from the box, then copy the entire URL address by triple (left) clicking to highlight it then right click and choose "Copy". Go back to your post and click on the IMG button. Hightlight the text "
http://put.url.here/image.file " that is not inside brackets. Make sure there are no spaces. Right click the highlight portion and choose "Paste".
That's all there is to it.