D5100 and Canon 500d - problem focusing

My friend with the D5100 went ahead and got a Canon 500d closeup lens.  But she is having some trouble with it.

She first tried it on her 18-55mm lens, and said it worked, but wasn't that close (which is logical).

The forum recommendation was to use it on her 55-200mm lens.  She tried that, but could not get it to autofocus at all.  She tried close to the object, and up to 6 feet away.  I think she final got a shot with the lens at 55mm from some feet away, but of course that wasn't much of a closeup.  Zoomed, she couldn't get the camera to focus at all.

Unfortunately, there are a few states between us, so I'm can't look at this myself.

Any ideas what the problem could be?  Guidelines as to how to use this thing?