Membership Plugin Does Not Show 2CO Button

I have the Membership plugin activated. We are using 2Checkout to handle payments and subscriptions but no payment button appears for it.

I have tested Paypal and A.net and those payment/subscribe buttons work fine.

I have deactivated all other plugins, switched to the twenty twelve theme and tried other different settings, but nothing works.

How do we get 2co setup and get the payment button showing?