I realize the correct directory to download Aurora builds would be http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-aurora-l10n/, but it does not have 64-bit Windows build which is unfortunately the only way to solve severe stuttering problems in Flash. Previously I had used nightly builds, while they did work fine most of the time sometimes there issues that forced me back to standard builds, and stuttering Flash. So instead I've been trying to use 64-bit Aurora I downloaded from http://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla-aurora/. It's been a smooth experience otherwise but auto-update doesn't work. First it attempts to install small patch, which fails. Then it tries to install full update, which again fails. Here's a screenshot of the full update failure message: http://i.imgur.com/8HmPjTE.jpg