Parallels 6 snapshot automation

The new Parallels 6 has a Backup panel in the configuration window. Here you can set up snapshots to be "optimized for Time Machine" or with a custom schedule (with frequencies from 1 to 24 hours).

What state does Parallels need to be in for these snapshots to be taken?

Will snapshots occur if Parallels is not running? ("yes" would seem to be the only useful answer)

I'm running an experiment to determine the answer, but this should be documented explicitly.