Still not working with 3.16-4, but fails with different errors:
786856.234:000f:0015:err:winediag:CorIsLatestSvc If this function is called, it is likely the result of a broken .NET installation
and
786856.237:000f:0015:err:eventlog:ReportEventW L".NET Runtime Optimization Service (clr_optimization_v4.0.30319_32) - Tried to start a service that wasn't the latest version of CLR Optimization service. Will shutdown\n"
Full log here
Game won't start. Proton 3.16-6 Beta.
System Info : https://gist.github.com/darcalus/708da494996a4e84312cc955fbd5bf62
Proton Log : https://gist.github.com/darcalus/56a33bcea9c48f4f7018cc4c1ca558d6
A Gold report appeared on ProtonDB a few weeks ago and I can confirm that the game does launch and is perfectly playable on Proton with the workaround described. Added my own report with more detailed instructions on how to get the game running. It seems the .Net installer provided by Steamworks Common Redistributables doesn't install properly.

steam-674520.log
The game is now fully working with no tweaks or workarounds with Proton 4.2-3.
Tried the game and i got this error (i have a 94MB log so pasting the important thing):
GL Bind Frame Buffer...Done!
OpenTK Implementation Initialized!
Running GameWindow!
1697.522:0026:0027:fixme:win:GetMouseMovePointsEx (16 0x32ed40 0x32e8f0 64 1) stub
1697.541:0026:0034:trace:loaddll:load_builtin_dll Loaded L"C:\windows\system32\hid.dll" at 0x778b0000: builtin
1697.541:0026:0034:trace:loaddll:load_builtin_dll Loaded L"C:\windows\system32\setupapi.dll" at 0x6dfe0000: builtin
1697.545:0026:0034:trace:loaddll:load_builtin_dll Loaded L"C:\windows\system32\xinput1_4.dll" at 0x778a0000: builtin
1697.546:0026:0034:fixme:rawinput:RegisterRawInputDevices Unhandled flags 0x2100 for device 0.
1697.546:0026:0034:fixme:rawinput:RegisterRawInputDevices Unhandled flags 0x2100 for device 1.
1697.546:0026:0034:fixme:rawinput:RegisterRawInputDevices Unhandled flags 0x2100 for device 2.
1697.548:0026:0034:fixme:win:RegisterDeviceNotificationA (hwnd=0x30058, filter=0xdfafaa4,flags=0x00000000) returns a fake device notification handle!
1706.673:0026:0027:trace:seh:__regs_NtGetContextThread 0x180: eax=fffffffc ebx=0dfaf2d8 ecx=00000002 edx=ffffffff esi=00000000 edi=0dfaf2d8
1706.673:0026:0027:trace:seh:__regs_NtGetContextThread 0x180: ebp=0dfaf178 esp=0dfaf100 eip=f7f5c929 cs=0023 ss=002b flags=00000282
[0000002C:] EXCEPTION handling: System.MemberAccessException: Object is busy and cannot state allow this operation [GDI+ status: ObjectBusy]Unhandled Exception:
System.MemberAccessException: Object is busy and cannot state allow this operation [GDI+ status: ObjectBusy]
at System.Drawing.GDIPlus.CheckStatus (System.Drawing.Status status) [0x000d6] in :0
at System.Drawing.Graphics.Dispose () [0x0003a] in :0
at (wrapper remoting-invoke-with-check) System.Drawing.Graphics.Dispose()
at System.Drawing.Graphics.Finalize () [0x00000] in :0
1706.696:0026:002c:trace:mscoree:CorExitProcess (ff)
1706.696:0026:002c:trace:mscoree:CLRMetaHost_ExitProcess 255
1706.697:0026:002c:trace:seh:__regs_NtGetContextThread 0x74: eax=fffffffc ebx=0032e940 ecx=00000001 edx=000003e8 esi=00000000 edi=00000000
1706.697:0026:002c:trace:seh:__regs_NtGetContextThread 0x74: ebp=79ab864c esp=0032e8e0 eip=f7f5c929 cs=0023 ss=002b flags=00000282
1706.699:0026:002c:trace:seh:__regs_NtGetContextThread 0x180: eax=fffffffc ebx=0dfaf2d8 ecx=00000002 edx=ffffffff esi=00000000 edi=0dfaf2d8
1706.699:0026:002c:trace:seh:__regs_NtGetContextThread 0x180: ebp=0dfaf178 esp=0dfaf100 eip=f7f5c929 cs=0023 ss=002b flags=00000282
1706.702:0026:002c:trace:seh:__regs_NtGetContextThread 0x180: eax=fffffffc ebx=0dfaf2d8 ecx=00000002 edx=ffffffff esi=00000000 edi=0dfaf2d8
1706.702:0026:002c:trace:seh:__regs_NtGetContextThread 0x180: ebp=0dfaf178 esp=0dfaf100 eip=f7f5c929 cs=0023 ss=002b flags=00000282
1706.702:0026:002c:trace:seh:__regs_NtGetContextThread 0x180: eax=fffffffc ebx=0dfaf2d8 ecx=00000002 edx=ffffffff esi=00000000 edi=0dfaf2d8
Using Proton 4.2-9 on ArchLinux
Información del equipo:
Fabricante: Unknown
Modelo: Unknown
Factor de forma: Sobremesa
Entrada táctil no detectadaInformación sobre el procesador:
Fabricante de la CPU: GenuineIntel
Marca de la CPU: Intel(R) Core(TM) i5-6600K CPU @ 3.50GHz
Familia de la CPU: 0x6
Modelo de la CPU: 0x5e
Stepping de la CPU: 0x3
Tipo de CPU: 0x0
Velocidad: 3900 MHz
Procesadores lógicos: 4
Procesadores físicos: 4
HyperThreading: No compatible
FCMOV: Compatible
SSE2: Compatible
SSE3: Compatible
SSSE3: Compatible
SSE4a: No compatible
SSE41: Compatible
SSE42: Compatible
AES: Compatible
AVX: Compatible
CMPXCHG16B: Compatible
LAHF/SAHF: Compatible
PrefetchW: No compatibleVersión del sistema operativo:
Unknown (64 bits)
Nombre de kernel: Linux
Versión de kernel: 5.1.15-arch1-1-ARCH
Editor de X Server: The X.Org Foundation
Versión de X Server: 12005000
Gestor X Window: GNOME Shell
Versión del runtime de Steam: jenkins-steam-runtime-beta-release_0.20190320.2Tarjeta de vídeo:
Controlador: NVIDIA Corporation GeForce GTX 1070/PCIe/SSE2
Versión del controlador: 4.6.0 NVIDIA 430.26
Versión de OpenGL: 4.6
Profundidad de color del escritorio: 24 bits por píxel
Frecuencia de actualización del monitor: 144 Hz
Identificador del fabricante: 0x10de
Identificador del dispositivo: 0x1b81
Revisión no detectada
Número de monitores: 1
Número de tarjetas de vídeo lógicas: 1
Resolución de pantalla principal: 1920 x 1080
Resolución de escritorio: 1920 x 1080
Tamaño de la pantalla principal: 20.91" x 11.77" (23.98" diag)
53.1cm x 29.9cm (60.9cm diag)
Bus principal: PCI Express 16x
Memoria VRAM principal: 8192 MB
Modos MSAA compatibles: 2x 4x 8x 16xTarjeta de sonido:
Dispositivo de sonido: Realtek ALC1150Memoria:
RAM: 15980 MBVarios:
Idioma de la IU: Español - España
IDIOMA: es_ES.UTF-8
Espacio total en disco disponible: 468427 MB
Bloque libre más grande en el disco: 257989 MB
Visor de RV: Ninguno detectado
steam-674520.log
with Proton 5.0-7 it sadly does not work
Unhandled Exception:
System.MemberAccessException: Object is busy and cannot state allow this operation [GDI+ status: ObjectBusy]
at System.Drawing.GDIPlus.CheckStatus (System.Drawing.Status status) [0x000d6] in <a3003ab57e8d46439df2e20f3cf113cd>:0
at System.Drawing.Graphics.Dispose () [0x0003a] in <a3003ab57e8d46439df2e20f3cf113cd>:0
at (wrapper remoting-invoke-with-check) System.Drawing.Graphics.Dispose()
at System.Drawing.Graphics.Finalize () [0x00000] in <a3003ab57e8d46439df2e20f3cf113cd>:0
This is caused by a known Mono bug that's been fixed Wine Mono 5.0.0. It should be solved next time we get a Wine Mono update in Proton.
proton 5.0-7x1 2020-05proton 4.2-9x1 2019-06proton 4.2-3x1 2019-04proton 3.16-6x1 2019-01hid.dllx1 2019-06setupapi.dllx1 2019-06xinput1_4.dllx1 2019-06
Compatibility Report
System Information
I confirm:
Symptoms
The game doesn't launch.
Reproduction
Try starting the game.