Shader compilation does not fail regardless of that message. Please record an apitrace (preferably on Windows) so that I can actually debug the game.
The game is rated Platinum on protondb by the way, please test whether an older DXVK version works.
Apologies for the delayed response, the application no longer freezes during launch and appears to work as expected including SteamVR mode (tested with Proton 4.11-11/DXVK 1.5)
@doitsujin The DxbcCompiler message still exists though not causing the original issue, sorry for the confusion.
proton 4.11-11x1 2019-12proton 3.16-6x1 2018-12
Software information
Thumper (Steam) freezes during launch process due to failed shader compilation:
DxbcCompiler: Unsupported custom data block: DxbcCustomDataClass::OpaqueOriginal Reference
System information
Log files