How do I create a full multisite snapshot?


I downloaded the Snapshot Pro plugin. It's awesome and so easy to use but there's one thing I can't figure out: how do I create a snapshot of the whole multisite environment (ie. main site + all subdomain sites)? It seems to only backup DB and files for the main site. I know there's an option to add snapshot for sub-sites but that looks like I can do one per snapshot setting.

If such a feature is not available, is there at least a way to allow the sub-site admins create their own snapshot schedules but apply global storage and number of snapshots settings set by main site admin?