I apologize for any issues trying to export your survey results. I went in to your account and was able to export the results without issue. What I noticed is after hitting "export" it will immediately send the file to your Downloads folder (I am using Chrome and it shows my downloads along the bottom of the browser -- other browsers might display it differently or not be as noticeable). Have you checked your download history on the browser itself?
Just in case here are the steps to export:
After hitting the export button that is when you should notice the file in your download history. If for some reason you have checked your download history or even your downloads folder on your computer and the export is nowhere to be found then reach out to us at social_support(at)constantcontact(dot)com with your username, the name of the survey you are trying to export from, the browser you are using, and a reference to this post and we can do additional troubleshooting to resolve the issue.