I can't get Aperture 3.4.3 to setup Flickr

Hi All,

Any ideas why I can't get Aperture 3.4.3 to setup and authorise against my Flickr account? When I press the Setup button, it opens the browser, logs me into my Flickr home page and then does nothing else. I have tried three different browsers; cleared cookies; cleared cache. I've even checked my Keychain based on information from other questions of the same nature.

I've even tried reinstalling Aperture, but no luck. I've tried this from Lightroom 4 and it works with no problem at all.

I'd be grateful if anyone could suggest something else to try

Incidentally, it authorises against Facebook again with no problem. It's just Flickr that's the problem.

Thanks