tulip911: I already have Witcher 3 installed and up to date on my computer. I installed it last year and finished it. I purchaced the game through GOG and am registered through GOG. Installed GOG Galaxy today and now its redownloading the whole stinking program!!!! WTF! I hope my save files will still be there. Not a very good 1st impression Gog Galaxy
There have been quite a few patches to the game and its DLC since it was released, if you just installed Galaxy then Galaxy will detect that the game is out of date and automatically update it to the current release by default. If you do not want it to do this, you need to disable auto-update for each game individually, however there is a bit of a catch-22 because if you install Galaxy, it will start updating your games before you get a chance to disable auto-update.
If you want to stay using an ancient version of the game then you can start up Galaxy, quickly click on the game and go to settings and disable auto-updates for it, then exit Galaxy. In theory that should terminate any update it was in the process of trying to do. Do that with each game you want to stay on an outdated version of.
Having said that, CDPR has fixed a tonne of bugs in the game and added a whole bunch of fantastic new features to the game since last year including revamping the user interface significantly. It's highly recommended to use the current version of the game (1.31) as it's significantly improved. If you don't want Galaxy to update it and prefer to do that yourself, after disabling auto-update for the game as per above, you can download the patches manually and install them, then start Galaxy after. That assumes you're using version 1.10 of the game or newer already, otherwise you will need to download the game's full installer instead as the only patches still available require version 1.10 or newer to patch.
Another thing worth noting is that there is a race-condition that can occur with Galaxy when it is running and you install a non-current version of a game from an old installer - even if you have patches for it. What happens is that any Galaxy-aware game installer will install the game and then invoke GalaxyClient to register the game with Galaxy. At that point if Galaxy is running it defaults to auto-update and will begin scanning the game's files to compare them with GOG's server and see if a new version is available. Galaxy has no idea if you already have the standalone patches or if you plan on installing them right now or an hour from now or ever, so it just happily goes ahead and starts updating the game for you.
The only solid way to prevent that, is to always install games from standalone installers like this:
1) Check to see if there are new installers or patches for the game than what you have downloaded already.
2) Download any new patches you are missing, or a whole new installer as appropriate. Do the same for any DLC etc.
3) Exit Galaxy completely.
4) Install the game.
5) Install all patches for the game.
6) Install any expansions and/or DLC for the game.
7) Install any patches for the expansions and/or DLC.
8) Start Galaxy, it should already be aware the game is installed if the installer was Galaxy aware. If it was a Galaxy non-aware installer then you'll have to do a manual import.
Galaxy will still try to scan the game and compare it and download a few things (DirectX et al), it's usually only a few megabytes to a few hundred megabytes even though it may say otherwise in the UI. Either let it do that or disable auto-update.
HTH