Configuring snapshot for multidomain back up

Hi

1. I have set up multidomain and now building the network sites.

2. Have set up snapshot & run a backup to Dropbox - all OK

3. Opening the files though, I see that it is only backing up the SQL tables for the main site "wp_xyz" and not any of the network sites - "wp_2_xyz", "wp_3_xyz" etc

4. Have not checked, but assume that am not getting themes, media backups for the networks either?

Cannot see in Snapshot set up where / how to configure this?

Thanks