@Snark I'm sorry. I do understand how troubleshooting works. The thing is, I don't have much to go on here. I was expecting a reply from somebody who might have the same issue or someone who found a fix. Game doesn't crash. It just sits there with a black screen, a yellow loading bar half filled and frozen with no text. Game itself is not frozen as it does respond to Alt+Enter. I tried the logs in AppData location and didn't find anything to suggest a problem. I can provide screenshot, but that won't show anything really. As I said, this particular issue is only for 64bit exe.
My system is an i7, 12gb or RAM, Nvidia 1060GT 6GB, Windows 10 64bit. Game is unmoded and installed about a week ago. Ran without any issue for 3 days. Game was also closed properly last time. I'm going to do a reinstall and see what happens. I'll let you know if the issue returns.