Can't download The Stanley Parable Demo

[Dachimotsu]

I already bought and have played the full game without a hitch. But I also want to be able to play the demo (which is completely different for those who don't know). But no matter what I try, clicking the button that says "Download Demo" or the banner that says "Play The Stanley Parable Demo Now" does absolutely nothing. I even tried running the Steam Repair using the Command Prompt like the Support section suggests, but no results. What do I do?