J'avais le meme problème...
Il faut autoriser le contenu flash à enregistrer des données sur ton pc :
"The best way to enable Flash Local Storage and verify your Flash settings, is to visit this online :
http://www.macromedia.com/...
This link will show you your web browser's actual global Flash configuration settings, beginning with the 'Global Storage Settings' tab, which has an icon featuring a file folder superimposed on a globe.
From here, make sure the "allow third party Flash content to store data on your computer" checkbox is checked. Next, drag the slider above that checkbox up to "100k" or higher.
Next, click the tab immediately to the right (the icon has a lock superimposed on a globe), which is 'Global Security Settings.' From here, select the "Always ask" option. "