Membership not displaying button on authorize.net checkout

Have membership 95% configured, works fine on paypal payments, but we want to use authorize.net instead. Have entered credentials, installed wildcard SSL, confirmed SSL serving on https://www.optionsideacentral.com/register/

The problem is, there are no BUTTONS on the checkout - the paypal subscribe is there, but nothing for authorize.net. I've tried sandbox and live mode. Disabling paypal. Everything I can think of, no joy.

Can you help?