I replied in the other thread where you had problems, but basically:
It's not working from flickr because it's a html page rather than an image. If you right click the image, and choose properties, then you'll see the link to the actual picture. Copy that and put it inside the [ i m g ] tags.
example:
http://www.flickr.com/photos/chrisdono/3553408423/
the picture is:
so you remove the ?v=0 bit and put the rest inside the [i m g] tags
You can also click on "all sizes", choose the size you want, and copy the link it gives you to the photo directly rather than the page.