Like when you open the game file. You will usually have a "game name.exe " or something like that to open the game but mine is "game name-32.exe". I can't play any games with a file that has the 32.exe thing
It's rather easier to download games using the Itch.io launcher; I've been using it for the past two years almost and it's much more easier to download the games and their updates; You can choose if you want to update the said games or not.
Yup! There’s an itch.io launcher free for download, just two clicks and it’s installed. Though you DO have to login in, but that shouldn’t be a problem. If it is, check if the servers are down or if the application is downloaded incorrectly (: Hope I helped