I installed the Abell catalog a long time ago, and now I just noticed that none of the items are showing up in KStars, not even if I search. I looked and see that it is listed as being installed. How do I delete it, and reinstall? I clicked on it to uninstall, but I cant reinstall it. I get an error message that states the due to a known bug, it's not possible to reinstall a new copy over the old one. But I cant delete the old one. What to do?