Im Having the same problem, i can deploy an windows 8.1 image but for some reason i cannot upload it. I get the same screen as the OP. Any progress on this?
Edit i fix my issue with a little google, someone else posted to use Part Magic and try to open the drive in the file viewer. When this happens it will tell you to run a command to remove the hibernated file. I did and boom fog is now uploading the image.