If you are having trouble processing your credit card during the pre-registration process, you should make sure that your Chrome browser is set up to enable third-party cookies.

1. Open Chrome Preferences, click on Settings, then Show Advanced Settings.
2. Under Privacy, click on Content Settings.
3. Make sure Block third-party cookies and site data is not checked

Once that is enabled, you should be able to enter your credit card and pay for the registration.