Box Backup isn't dead, but there is pretty much only one guy maintaining the code these days and he doesn't get time to release very often.
It's good software but still not really feature-complete. For example, doing mass-restore (e.g. an entire directory) is very tedious. Single files are fine, but this doesn't make it very useful.
(Point of note, I maintain the servers for the project, but don't really contribute to the project itself these days.)