I'm having an issue with applying a coupon. When I click "Apply coupon" on /signup, the page refreshes and goes back to the version of the /signup page that lists all the subscriptions.
You can test it here:
Choose SEASON 1 DIGITAL & PRINT U.S. $8. First you'll have to create an account and then try adding the coupon code FREEBIE8.
I'm running Version 184.108.40.206 of the plugin and Wordpress Version 3.6.1.