Catgirl
Published
When Borderlands 2 got the new DLC tie-in for Borderlands 3, only the Windows version was updated. Therefore, in the "Borderlands 2 - Properties" dialogue, check "Force the use of a specific Steam Play compatibility tool" to download the Windows version instead of running native.
The launcher doesn't run, so you'll want to skip it by swapping the Launcher.exe with Borderlands2.exe or making a symlink or whatever other method you prefer.
D9VK is required to avoid rendering glitches. If you experience poor performance or out of memory crashes, disable esync and force large address aware, respectively. I also use gamemoderun from https://github.com/FeralInteractive/gamemode for maximum performance, but this isn't required.
The final launch options with all of these tweaks combined is "PROTON_USE_D9VK=1 PROTON_FORCE_LARGE_ADDRESS_AWARE=1 PROTON_NO_ESYNC=1 gamemoderun %command%"
First, you need a 32-bit wineprefix to install ie8 with winetricks, because the custom launcher uses embedded internet explorer. (Currently Proton doesn't crash on loading a 32-bit wineprefix, so don't mess with Steam's proton system files.) Then, you need to set Windows XP mode in winecfg for the BYOND account login or registration button to work.
After you've successfully connected your BYOND account to Steam and the custom launcher is giving you the options to run the game, you can return winecfg to Windows 7 mode if you prefer. You're probably going to get incredibly poor performance either way. It doesn't seem like the launcher can properly enable hardware rendering.
If you know what BYOND is and can get it running better in Wine directly, the launcher should unpack the BYOND game file to "steamapps/compatdata/249550/pfx/drive_c/users/steamuser/My Documents/BYOND/MyHub/silkgames/nestalgia/", but only users who have purchased it via BYOND or Steam will be able to log-in and play (so it's not 100% DRM-free). Good luck.
