If update fails, re-trying should try already-downloaded update first

[Chris Hanson]

When an update is downloaded but installing the update fails (say with a crash), the next time you try to update Sparkle should first attempt to use the already-downloaded update if it still exists, is still the latest, and its signature is intact.

[Andy Matuschak (andymatuschak)]

Very true. I won't get to it anytime soon, though, I'm afraid.

[Stuart Morgan (stuart-morgan)]

This would also help the case where someone downloads the update but typos their password while trying to authorize (there's apparently only one try, then you have to re-download), which a Camino user on a satellite connection has complained about.