The email address is not needed to setup the gateway, so it's greyed out to protect another part of the code that checks this field. But there should be a api, secret key and widget field at the bottom of the form. Could you please PM me an database export of your "donate_gateways" database table so I can check over this?
This is a confirmed bug. i may be able to patch this within the acp but I would need to look, otherwise this will need to wait until the next version.