Deleting stuff from the Shelf

[dapperdanman1400]

Hi, I'm new to using Quicksilver.  I just started messing around with
the Shelf, and I ended up adding a bunch of stuff to it that I didn't
want to.  I read in the how-to that just selecting the item and
pressing the delete key would get rid of it, but alas, that didn't do
anything. I tried the Fn + Delete, but that did nothing either (I'm on
a MacBook Pro running Leopard by the way).  Any thoughts?