The first time I played a game after creating an online account, it got stuck at “Uploading to Bletchley Park”. I alt-tabbed and it stopped responding completely so I had to terminate the process.
Are you sure that a firewall or other internet software is not perhaps blocking the game? If possible, try to run the game in a window next time, and if it hangs again, you can easily see if there is a pop-up from firewall or security software asking for permission.
Nope, no popups and this time it worked