Snapshot for multiite

Hi All,

I use the WP 3.5.1 (multisite) and I would like to use the snapshot plugin for backup my whole site however I found some problems as below:

1. I found that it's able to backup only the primary site.
Do I need to config or setup something more?

2. During I'm restoring the old version, the processes are frozen. Then, I refresh and found that I can't see any backup zip files via snapshot plugin. By the way, the backup files still exists. I tried to reactivate / reinstall the snapshot plugin but it still not work.
Do you know the way to fix it?

For more information, I use appserv to make my pc as the server for testing.

Please help?