I have updated the image widget to the latest version. 4.0.6
But I still have the same problem. When I try to change the current image in the widget, I get a pop-up wichs shows my medialibrary. Strange thing is that this one is empty. If I access it in wordpress itself i see all my media. Now when I try to upload a new image within the widget, it uploads the image, but at the end it gives an error saying that something went wrong. Now when I go back to the media library in wordpress, i can see the image I just uploaded. But there is no way I can get it within the widget itself. I still see my old image that I uploaded before the big update to wordpress 3.5
Please help me to fix this.