How can I migrate my multisite blogs from one network

How can I migrate my multisite blogs from one network to another (different domain names)? I've tried the recommended steps below:

1. New install of WP multisite.
2. Install Snapshot on new site and copied snapshot of existing primary site to /wp-content/snapshots/uploads.
3. Imported snapshot.
4. Attempted restore of imported snapshot to new primary site. This completes OK.

I then get error establishing database connection.

What am I doing wrong?

Thanks,

Michael