I don’t get that Installer thing ? Steam downloads the game executable as well as all of it’s required libraries and assets into the steamapps directory and runs install scripts. It also runs potentially needed dependency installers like c++ visual studio redistributables or directx installers. The same thing does the GOG installer. And the games I own on GOG have always had version parity with the steam versions. I thought this would be the standard if a publisher publishes on both stores.