Tarepsed: Same for me as well. Booted the computer, updated the game, and played several levels, before I noticed that the game didn't want to turn down the music volume. Back to menu, and all my progress was lost as well. I have Full ownership and access to my folders, but it just doesn't seem to to any good. Trying to delete and reinstall now.
edit: NVM. I noticed that it was my damn BitDefender which was blocking programs from writing to my Documents folder... You might want to check out your AV..
This ^^^^^^^^^^^^^^^^^^^^ this is exactly the issue. I turned off bitdefender and it then allowed me full gane access.