How to download full-size Flickr photos? Try jzlab’s Flickr Original 1.0.1 for Firefox. Install the addon, then restart Firefox, mouse over the image and right click in Flickr as shown in the image below and select – ‘Download Original Flickr Image’
I believe the ‘Flickr Original’ addon also works for those having problem downloading images protected by spaceball.gif. Visit this article for a step by step tutorial on how to download photo or images from Flickr.com that is protected by spaceball.gif.