Hey Dargo,

sometimes the yubikey confirmation does not work. I'm not sure if the problem is the yubikey or if there is another problem.
But when I want to confirm a withdrawal it happens often (~20% of the time), that I get the message "the submitted form has expired" (or something like this, I did not copy the exact wording), even though not more than 15 seconds have passed. 
Nonetheless the bitcoins were send.   So now it happens,that I thougt the bitcoins were not send and send the amount twice.
Luckily it was one of my addresses so i can send the bitcoins back. But what if it was not my address? So you should fix this issue.