Edit: This posted twice on accident.

I accidentally downloaded a game that includes GOG Galaxy. I forgot to choose to use the 'Download Classic Installer'.

My question is, am I able to disable GOG Galaxy on the version I downloaded that includes GOG Galaxy? I don't want the overlay or anything with GOG Galaxy and I was wondering if it's easy to disable/get rid of the GOG Galaxy on a game that includes it?

There's a checkbox you have to unchecked when you run the installer.

You could always uninstall the entire game and redownload and install the Classic Installer version.

So, that will not install GOG Galaxy at all or will it just disable it and it'll still be in the "background" so to speak?

Okay. Thank you very much.

It will not install Galaxy at all if you deselect the respective option during installation. And even with Galaxy installed you can still play your (single player) games without running Galaxy by double clicking the games executable in the install folder.

Galaxy is only ever needed for the multiplayer part of certain games. And the soon to be removed Gremlins Inc., good riddance!

Do be aware however, if you keep the galaxy bundled installer the file size is 150mb bigger than non-galaxy bundled one, and you have to remember to select that option each time. Me, I would go with re-download if possible to avoid these two issues and show to the metrics recorders that classic installers are being used - otherwise they will just drop them down the line when gog thinks we enough people have forgotten.