Firstly, you can tell if your PAGE has been accessed by the plays/downloads stats.
By sending a PAGE to only 1 person, you can then tell if they have played or downloaded from your PAGE.
Secondly, you can check your Download stats by clicking 'Export Collected Emails' from the PAGEs set up area.
This is will work for everyone who has used 'Download All' and also for individual Downloads if you have 'Request email addresses in exchange for Downloads?' enabled.