Themeroller download not working?

Themeroller download not working?

I am trying to use Themeroller for the first time and can not get the download function to work.
When I click the [Download Zip] button nothing happens.
I'm using a Windows 7 PC running the latest version of Chrome and Firefox and get the same result in both browsers. There is no error and the browser doesn't appear to be doing anything.
Any guidance or advice would be appreciated.