update: got shelf and clipboard in all places that i was supposed to get it (i mean, in catalog, quicksilver window). It will sound stupid but i m absolutely certain that it happened as soon as i clicked on "shelf" in the "plugins" menu in the menu bar. I had never before had the menu bar active for quicksilver, so i had never before clicked "shelf" in the menu in menu bar.
And one more thing Howard, you might want to know: there are still no files in the shelves folder. The size of shelves folder is zero KB. Thanks.
