Nice! Looking quite good.

Finally, did you manage to run the game?

I don’t exactly remember, but I know that I had the launcher running for the first times, and in it, I disabled it so the game launches right away.

One thing I had in a different game, was a edge process (certainly to fetch news or something) that failed and that was the process I had to kill so I could see the launcher.
I use btop in the terminal to show processes and I filter with the approximate name of the process I want.
If you don’t know the executable name, you can filter steam and it’ll show steam and the sub-processes that are running.
From there, you can simply select edgeUpdate ( I think that was that) or DirectXInstall (both used to cause me problem when launching games for the first time) and use the kill button and see if the game launches.

I think I recall having issues with Proton Experimental.
I think I am using the last stable Proton 8.something.
Tried the last GE-Proton as well but also had some issues.

Another thing, I think during the first launch, some Directx installs did fail or took long and I killed the processes.
Though, the game always started fine for me, and I disabled the Launcher at the first occasion, now all is good.

Also, I had some other issues with Steam lately, and I tried the Beta version of the client, all my issues are fixed, you could try that as well.

Maybe you can do something like that in the launch options:

xbindkeys <stuff> && %command% && pskill xbindkeys

I don’t remember the game run command but it should be similar to %command% or something…