The most common reason for not receiving your download is an incorrect email address was entered. Double check to make sure you received an initial receipt from us. If you didn't, please email us at firstname.lastname@example.org so we can correct the email for you.
If your email was entered correctly: it can take a few minutes for the download to process through our system. If after 10 minutes you still haven't received your download email, please email us so we can make sure everything processed correctly.
Also try going into your spam filter and searching for the message. Sometimes overactive spam filters can prevent you from getting emails.