I'm setting up Subscriptions for a client; I've implemented the Subscriptions page, and it works for people who already have an account in EE, but it fails if you aren't logged in, despite register_member="yes" being set.
The error returned is:
CARD_CREATE: Email is required.
I verified that the email address is indeed in the form, and in fact, I get this error even with the Templates that come with Subscriptions. This makes the product unusable for my client.
If it matters, I also am using SolSpace User, and I have it set up to use email addresses as usernames on the site.