I've tried to use Snap in Ubuntu 11.10 but it doesn't work: when trying to create a backup (repos, packages and services) using the GUI, it freezes and it creates a backup archive of 19.1kb (it's always this size). Unfortunately, no matter what I select under "log level", I only get "Creating snapshot" so I don't have the any error output to show you...

I've tried both the .deb (which is pretty old, maybe you can update it?) and the latest code via GitHub.