I am having a bizarre problem! Hoping someone here can help me out. I have been trying to download third-party screensavers like these awesome ones, but am running into some issues. When I clock on the .saver icon, it seems to install properly. However, oddly enough, when I go to the screen saver preference pane, the screensaver is blank! Either plain black or plain white. The preview is blank as well. When I try to click options, it gives me a blank screen. I'm having this problem on my brand new 21.5" iMac (purchased today, yippee!). All the pre-installed mac screensavers function just fine. When I try the problematic third party ones on my old black macbook (Snow Leopard), no issues at all. Is this some sort of resolution problem? Your suggestions will earn my immense gratitude.