What do you need the security cert for?
I needed the cert so my installs would display my business name not 'unknown publisher' but I seem to be not the only one having trouble with the instructions chosensecurity/trustcenter deliver with their certificate:
Their recommended 'Doubleclicking on the downloaded file' appears to lead to a complex, and possibly unsuccessful process on the Mac.
However following the instructions on the above forum page I imported the certificate into Firefox and it worked fine using the Flex 4 beta.
I'm not sure if it works the same in Safari but it was certainly easy and perhaps is a better process to advise their Mac customers.
Your problem is solved, right?
Safari uses Keychain to maintain the certificates I belive. So it goes back to Keychain Access.
Firefox has been consistent and is allowed to export the full certificate chain. That is why we document this way.
Yes solved. The firefox process was much easier