I purchased the game and downloaded to my windows PC. Now when I play it tells me that I need to update to a newer version. Where in the world do I update the Game? The option isn't in the properties of the file. And I don't see a link to update this game anywhere.
Does it say v2020.11.17i in the top left corner when you open the game? That is the most recent version. Make sure you're looking at the right file after you download it. You might be accidentally opening the wrong one.
If you're having trouble downloading the game from itch.io, add the game to Steam with the key on your download page. It'll update automatically from there. You could also use the itch.io app if you don't want to use Steam.