[Compat]: Conan Exiles Enhanced Fails To Launch Using Proton-CachyOS-SLR

[blosseh]

Game name

Conan Exiles Enhanced

Steam AppID

440900

Proton-CachyOS version

11.0-20260429

GPU

AMD 7900XTX

Video driver version

Mesa 26.0.6-arch2.2

Kernel version

7.0.3-1

Full system information report

https://gist.github.com/blosseh/fa91a444270b3560834e746428725a51

Please confirm the following before submitting

• I haven't found an existing compatibility report for this game.
• I have checked whether there are updates for my system available.
• I have verified the issue is present when using Proton-CachyOS-SLR from this repository.
• I haven't encountered this issue using an official Proton release (Proton, Proton Experimental, or Proton Bleeding Edge).

Symptoms

Conan Exiles Enhanced immediately crashes upon launch when Proton-CachyOS-SLR is selected.
The issue does not occur when Proton-Experimental is used.

Steps to reproduce

1. Launch the game via steam with Proton-CachyOS-SLR selected.
2. Game does not launch (Button immediately reverts to "launch" after a few seconds)

Fix:
1.Launch the game via steam with Proton-Experimental selected.
2. Game launches.

Log from Proton-CachyOS-SLR

steam-440900_CACHYOS_PROTON.log

Log from recent Proton Experimental

steam-440900_PROTON_EXP.log

Log from Proton-CachyOS Native (if relevant)

No response

Additional context

Due to file upload size restrictions, the Proton Experimental log file is limited to the first 200,000 lines.

The game also does not launch on the following:
GE-Proton10-34
Proton-CachyOS-10.0-20260425-SLR-X86_64_V4
Proton-EM-10.0-37-HDR

I can confirm that ticking "Disable Battleye" in the launcher is a persistent option and having Battleye disabled in that way still results in the game not launching on custom proton versions.

[adamstirk-ct]

The ConanSandbox.exe doesn't exist, it's now ConanSandbox_BE.exe I've added this to my launch options to fix it %command% -pf_replace_cmd=FuncomLauncher.exe=../ConanSandbox/Binaries/Win64/ConanSandbox_BE.exe

[loathingKernel]

What the hell? And how does that work with Proton Experimental without needing the exe override? I am looking for any related changes and I cannot find anything. I am very confused.

Edit: I forgot, thanks for posting the workaround, much appreciated.

[adamstirk-ct]

I believe umu-protonfixes redirects the launcher away from FuncomLauncher.exe to ../ConanSandbox/Binaries/Win64/ConanSandbox.exe my guess is that that Proton Experimental doesn't use this.

https://github.com/Open-Wine-Components/umu-protonfixes/blob/490f51384d7f29cd4be2c26d84aaf2dec5d53b35/gamefixes-steam/440900.py

[loathingKernel]

Now I feel stupid, I did not even consider checking what protonfixes could be doing. Thank you for looking into it, one less headache.

Edit: protofixes can also be disabled using PROTONFIXES_DISABLE=1 which should also work until protonfixes is updated.