Why are all of my forms freezing on the first card?

After the welcome card, the very first card with a question freezes -- its a yes/no card and the buttons can be clicked but the card will not advance to the next card no matter what I do. This happens in preview mode as well as the published form. It seems to be happening to my card-layout forms but not my classic-layout forms. And -- its happening to ALL of my card-layout forms!

Does anyone have any ideas I can try to diagnose this? I'm kind of dead in the water until this gets fixed.

Any help is greatly appreciated... Thanks.

We are truly sorry for the inconvenience this has caused. The problem is now fixed. Your form should work fine now.

Fantastic! Thank you.