I suspect something happens on the itch.io backend where it doesn't download it properly. but trying again should fix it
I experience such problems in some games. In addition, I have downloaded two extraction programs, Winrar and 7zip, and I use both of them. If it doesn't work properly and gives the same error, I am sure that the problem is entirely due to the mistake of the person who installed the game. I tried what you said yesterday and ran it as administrator, it gave the same error. I will delete the game and reinstall it. I will run it with both winrar and 7zip and see if the problem persists. Thanks.