I'm attempting to download Yosemite from the Mac App Store. It's downloading, but when it gets to 870 MB, it pauses and drops back down to 860 MB and repeats indefinitely. I've signed out and back into the store, I've closed the application, I've searched ~/Library/Application Support/AppStore for partial downloads to delete, and there's no partial download. The data must be somewhere, though I can't find it, even with a smart folder. Where is it? How can I reset my download and try again? Thanks!