movingcastle: Writing to this thread because it helped me to enjoy multiple GOG games on Steam Deck with full functionality like cloud saves and achievements.
There are some important changes to this method. First of all:
* If you already have a working setup Steam Deck + GOG Galaxy that allows you to install and play GOG games with cloud saves and achievements, DON'T UPDATE GALAXY when it asks you to. This was the thing that broke my experience.
* If you follow the guide above, it won't work now. GOG Galaxy installation will throw an error at the end, which says "Essential components needed to start GOG Galaxy are missing....". Then you can launch and try to install games, but from my experience all games will fail to install with their own error, so they cannot be played.
The problem is with versions. To make the above guide work, you will need to used not the Proton Experimental, but Proton 9.0-3. I can confirm it works with GOG Galaxy version "2.0.80.33 - Beta". However, Proton 9.0-3 is not by default on Steam Deck. So before you attempt Galaxy installation you have to:
1. go to
https://github.com/Kron4ek/proton-archive/releases 2. download the archive "proton-9.0-3.tar.xz"
3. follow readme to install proton 9.0-3 on Steam Deck:
https://github.com/Kron4ek/proton-archive 4. (Optional) If you have a pre-existing Galaxy installation, delete it using the method described in this thread (have I already said this thread is gold?), i.e. delete the respective subfolder (a number much longer than any native Steam game you have) from "compatdata/"
5.follow the Galaxy installation guide here, but in the third step, Compatibility, when you check "Force the use of a specific Steam Play compatibility tool", instead of Proton Experimental select "Proton 9.0-3" (or however you called it on your system) from the list.
Then proceed with Galaxy installation.
Other tips, especially if you are using the Steam Deck as is, without any external input devices like keyboard or mouse:
* Due to the copying/pasting required it is easier to do the preparation of Galaxy installation and installation in Desktop mode
* When Galaxy installs you can steer the path to GalaxyClient.exe using file system, but i think selected somewhere in file explorer settings to show hidden folders, because /home/.steam is a hidden holder. Also I use "..." to wrap the path, because You will have to copy the path to
* The first launch of Galaxy is much easier in Gaming Mode because you will need to enter the username / password / 2FA.
* When in Galaxy, use STEAM button to access settings for the game (which is GOG Galaxy here) config your right trackpad to work as mouse. Then config the press of the right trackpad to be the left click of the mouse. This makes navigating the Galaxy, installing and launching games a blast. Otherwise you have to use touchscreen to click rather small buttons, scrolling your lib can be especially hard.
That's it. Good luck! I am still hoping to see some official Steam Deck support, even if it is in the format like the guides in this thread from the GOG Galaxy team.
I'm having an issue getting proton-9.0-3 to install.
I've followed the guide from github.com/Kron4ek/ creating the dirs, .vdf etc, steam appeared to install it whhen reloaded but 9.0-3 doesnt appear in my Compatability list.
If I run ProtonGE, it shows 9.0-3 as "unused" but I cant install it from there