With Proton 7.0.1, this should now be playable. I'm trying to run it with the standalone client launched through Steam with Proton so I can get back into my old account, so I'm not sure if this is relevant here.
It's installed and fully patched, and I can log in with the launcher. However after logging in, the ToS pops up and requires me to click the agree button before being able to launch the game. If I click it, the launcher crashes and the ToS still pops up the next time I try to log in.
(steam:89380): Gtk-WARNING **: 06:10:30.200: gtk_disable_setlocale() must be called before gtk_init()
(steam:89380): GLib-CRITICAL **: 06:10:30.200: unquote_string_inplace: assertion 'err == NULL || *err == NULL' failed
GameAction [AppID 2691235131, ActionID 3] : LaunchApp changed task to SiteLicenseSeatCheckout with ""
GameAction [AppID 2691235131, ActionID 3] : LaunchApp changed task to CreatingProcess with ""
GameAction [AppID 2691235131, ActionID 3] : LaunchApp waiting for user response to CreatingProcess ""
GameAction [AppID 2691235131, ActionID 3] : LaunchApp continues with user response "CreatingProcess"
/bin/sh\0-c\0/home/user/.local/share/Steam/ubuntu12_32/reaper SteamLaunch AppId=2691235131 -- '/home/user/.local/share/Steam/steamapps/common/SteamLinuxRuntime_soldier'/_v2-entry-point --verb=waitforexitandrun -- '/home/user/.local/share/Steam/steamapps/common/Proton 7.0'/proton waitforexitandrun "/home/user/.local/share/Steam/steamapps/compatdata/2691235131/pfx/drive_c/Neople/DFO/NeopleLauncher.exe"\0
Game process added : AppID 0 "/home/user/.local/share/Steam/ubuntu12_32/reaper SteamLaunch AppId=2691235131 -- '/home/user/.local/share/Steam/steamapps/common/SteamLinuxRuntime_soldier'/_v2-entry-point --verb=waitforexitandrun -- '/home/user/.local/share/Steam/steamapps/common/Proton 7.0'/proton waitforexitandrun "/home/user/.local/share/Steam/steamapps/compatdata/2691235131/pfx/drive_c/Neople/DFO/NeopleLauncher.exe"", ProcID 96182, IP 0.0.0.0:0
chdir /home/user/.local/share/Steam/steamapps/compatdata/2691235131/pfx/drive_c/Neople/DFO/
GameAction [AppID 2691235131, ActionID 3] : LaunchApp changed task to Completed with ""
ERROR: ld.so: object '/home/user/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
(steam:89380): Gtk-WARNING **: 06:10:30.240: gtk_disable_setlocale() must be called before gtk_init()
(steam:89380): GLib-CRITICAL **: 06:10:30.240: unquote_string_inplace: assertion 'err == NULL || *err == NULL' failed
ERROR: ld.so: object '/home/user/.local/share/Steam/ubuntu12_64/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS64): ignored.
ERROR: ld.so: object '/home/user/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
(steam:89380): Gtk-WARNING **: 06:10:30.250: gtk_disable_setlocale() must be called before gtk_init()
(steam:89380): GLib-CRITICAL **: 06:10:30.250: unquote_string_inplace: assertion 'err == NULL || *err == NULL' failed
ERROR: ld.so: object '/home/user/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
ERROR: ld.so: object '/home/user/.local/share/Steam/ubuntu12_32/gameoverlayrenderer.so' from LD_PRELOAD cannot be preloaded (wrong ELF class: ELFCLASS32): ignored.
pid 96186 != 96183, skipping destruction (fork without exec?)
fsync: up and running.
wine: RLIMIT_NICE is <= 20, unable to use setpriority safely
ThreadGetProcessExitCode: no such process 96336
ThreadGetProcessExitCode: no such process 96334
ThreadGetProcessExitCode: no such process 96184
[S_API FAIL] SteamAPI_Init() failed; no appID found.
Either launch the game from Steam, or put the file steam_appid.txt containing the correct appID in your game folder.
MESA-INTEL: warning: Haswell Vulkan support is incomplete
WARNING: radv is not a conformant Vulkan implementation, testing use only.
MESA-INTEL: warning: Haswell Vulkan support is incomplete
WARNING: radv is not a conformant Vulkan implementation, testing use only.
ThreadGetProcessExitCode: no such process 96339
MESA-INTEL: warning: MESA-INTEL: warning: Haswell Vulkan support is incompleteHaswell Vulkan support is incomplete
WARNING: radv is not a conformant Vulkan implementation, testing use only.
WARNING: radv is not a conformant Vulkan implementation, testing use only.
MESA-INTEL: warning: MESA-INTEL: warning: Haswell Vulkan support is incompleteHaswell Vulkan support is incomplete
WARNING: radv is not a conformant Vulkan implementation, testing use only.
WARNING: radv is not a conformant Vulkan implementation, testing use only.
Crash Annotation GraphicsCriticalError: |[0][GFX1]: Potential driver version mismatch ignored due to missing DLLs 0.0.0.0 and 0.0.0.0 (t=46.3449) [GFX1]: Potential driver version mismatch ignored due to missing DLLs 0.0.0.0 and 0.0.0.0
wine: Unhandled page fault on read access to 00000000 at address 10144B38 (thread 0140), starting debugger...
Unhandled exception: page fault on read access to 0x00000000 in 32-bit code (0x10144b38).
Register dump:
CS:0023 SS:002b DS:002b ES:002b FS:0063 GS:006b
EIP:10144b38 ESP:00a4d5c8 EBP:00a4d634 EFLAGS:00210202( R- -- I - - - )
EAX:00000000 EBX:00000000 ECX:00000000 EDX:00000000
ESI:00a4d5d0 EDI:00a4d5d4
Stack dump:
0x00a4d5c8: 00000000 10c99bc8 00000000 00000000
0x00a4d5d8: 00c08230 00a4d658 00000000 10c9abc8
0x00a4d5e8: 00c08230 10c9a21b 00c08278 10c97989
0x00a4d5f8: 26494bf0 00c08278 00000000 00000032
0x00a4d608: 100b5355 00000032 00000000 00c08278
0x00a4d618: 00c08348 00a4d638 00a4d6a4 10c9c647
Backtrace:
=>0 0x10144b38 EntryPoint+0x1439a8() in xul (0x00a4d634)
1 0x10c9b9ea EntryPoint+0xc9a85a() in xul (0x00a4d6a4)
0x10144b38 xul+0x144b38: movl 0x0(%ecx),%eax
Modules:
Module Address Debug info Name (70 modules)
PE 00140000-0019c000 Deferred combase
PE 00400000-0084e000 Deferred neoplelauncher
PE 00fc0000-01088000 Deferred winmm
PE 01ab0000-01ab8000 Deferred api-ms-win-crt-heap-l1-1-0
PE 01ac0000-01ac9000 Deferred api-ms-win-crt-string-l1-1-0
PE 01ad0000-01ad8000 Deferred api-ms-win-crt-utility-l1-1-0
PE 01ae0000-01aed000 Deferred userenv
PE 01af0000-01b20000 Deferred uxtheme
PE 023e0000-024dd000 Deferred mozglue
PE 043f0000-045ff000 Deferred nss3
PE 063d0000-064e3000 Deferred lgpllibs
PE 10000000-15654000 Export xul
PE 3b400000-3b438000 Deferred steam_api
PE 61500000-6152f000 Deferred iphlpapi
PE 61740000-61784000 Deferred advapi32
PE 61940000-619cd000 Deferred wininet
PE 61f00000-61f09000 Deferred api-ms-win-crt-convert-l1-1-0
PE 61f80000-61f8b000 Deferred api-ms-win-crt-math-l1-1-0
PE 62d40000-62d47000 Deferred api-ms-win-crt-environment-l1-1-0
PE 62fc0000-6304e000 Deferred rpcrt4
PE 631c0000-631e1000 Deferred secur32
PE 63480000-6348d000 Deferred version
PE 63740000-63749000 Deferred api-ms-win-crt-runtime-l1-1-0
PE 637c0000-63869000 Deferred urlmon
PE 63bc0000-63bda000 Deferred shcore
PE 64a40000-64a94000 Deferred shlwapi
PE 64ec0000-64fee000 Deferred oleaut32
PE 65d40000-65d48000 Deferred api-ms-win-crt-filesystem-l1-1-0
PE 65f40000-65f4d000 Deferred kerberos
PE 66240000-66258000 Deferred bcrypt
PE 66600000-66607000 Deferred api-ms-win-crt-locale-l1-1-0
PE 66b00000-66b3e000 Deferred win32u
PE 67840000-6784a000 Deferred psapi
PE 67ec0000-687f8000 Deferred shell32
PE 688c0000-688ea000 Deferred netapi32
PE 69180000-69190000 Deferred wsock32
PE 69480000-694ad000 Deferred mlang
PE 6a040000-6a062000 Deferred msacm32
PE 6a280000-6a32e000 Deferred msvcrt
PE 6a400000-6a533000 Deferred ole32
PE 6aa40000-6aa48000 Deferred usp10
PE 6b7c0000-6b7c9000 Deferred api-ms-win-crt-stdio-l1-1-0
PE 6bc00000-6bc2c000 Deferred sechost
PE 6bcc0000-6bd40000 Deferred setupapi
PE 6c9c0000-6ca45000 Deferred gdi32
PE 6cc40000-6cd9e000 Deferred comctl32
PE 6cf40000-6cf47000 Deferred api-ms-win-crt-time-l1-1-0
PE 6d780000-6d7a8000 Deferred ws2_32
PE 6dd00000-6dd0c000 Deferred schannel
PE 6e3c0000-6e479000 Deferred jscript
PE 6e4c0000-6e4d6000 Deferred dnsapi
PE 6e8c0000-6e995000 Deferred crypt32
PE 6ec40000-6ec4e000 Deferred dwmapi
PE 6ed00000-6ef41000 Deferred user32
PE 6f480000-6f48c000 Deferred nsi
PE 6f4c0000-6f4e8000 Deferred wintrust
PE 6f600000-6f60a000 Deferred api-ms-win-crt-multibyte-l1-1-0
PE 6f700000-6f789000 Deferred ieframe
PE 6f900000-6f93c000 Deferred msctf
PE 6fe40000-6fe74000 Deferred rsaenh
PE 6ff00000-70113000 Deferred mshtml
PE 702c0000-702d7000 Deferred api-ms-win-crt-private-l1-1-0
PE 70940000-70960000 Deferred mpr
PE 70b40000-70c1c000 Deferred ucrtbase
PE 70e80000-70e8a000 Deferred msimg32
PE 71200000-7121c000 Deferred imm32
PE 7b000000-7b0ec000 Deferred kernelbase
PE 7b600000-7b81a000 Deferred kernel32
PE 7bc00000-7bca8000 Deferred ntdll
PE f60e0000-f60e4000 Deferred winex11
Threads:
process tid prio (all id:s are in hex)
00000020 steam.exe
00000024 0
000000c8 0
00000148 0
00000030 services.exe
00000034 0
00000038 0
00000044 0
00000054 0
00000068 0
00000074 0
00000098 0
000000b0 0
00000100 0
0000003c winedevice.exe
00000040 0
0000004c 0
00000050 0
00000058 0
0000005c 0
000000bc 0
00000060 winedevice.exe
00000064 0
0000006c 0
00000070 0
00000078 0
0000007c 0
00000080 0
00000084 0
0000008c 0
00000090 plugplay.exe
00000094 0
0000009c 0
000000a0 0
000000a4 0
000000a8 svchost.exe
000000ac 0
000000b4 0
000000b8 0
000000c0 conhost.exe
000000c4 0
000000cc explorer.exe
000000d0 0
000000e0 0
000000ec 0
000000f4 rpcss.exe
000000f8 0
00000108 0
0000010c 0
00000110 0
00000114 0
00000128 0
00000154 0
0000012c tabtip.exe
00000130 0
00000138 0
00000144 0
0000013c (D) C:\Neople\DFO\NeopleLauncher.exe
00000140 0 <==
0000014c 0
0000015c 0
00000160 0
00000164 0
00000168 0
0000016c 0
00000170 0
00000174 0
00000178 0
0000017c 0
00000180 0
00000184 0
00000188 0
0000018c 0
00000190 -1
00000194 -1
00000198 0
0000019c 0
000001a0 0
000001a4 0
000001a8 0
000001ac -1
000001b0 0
000001b4 0
000001b8 0
000001bc 0
000001c0 0
000001c4 0
000001c8 0
000001cc 0
00000224 0
00000228 0
00000230 0
0000023c 0
System information:
Wine build: wine-7.0
Platform: i386 (WOW64)
Version: Windows 10
Host system: Linux
Host version: 5.16.10-201.fsync.fc35.x86_64
ThreadGetProcessExitCode: no such process 96499
ThreadGetProcessExitCode: no such process 96427
ThreadGetProcessExitCode: no such process 96409
ThreadGetProcessExitCode: no such process 96378
ThreadGetProcessExitCode: no such process 96372
ThreadGetProcessExitCode: no such process 96366
ThreadGetProcessExitCode: no such process 96344
ThreadGetProcessExitCode: no such process 96341
ThreadGetProcessExitCode: no such process 96335
ThreadGetProcessExitCode: no such process 96333
pid 96337 != 96336, skipping destruction (fork without exec?)
Game process removed: AppID 0 "/home/user/.local/share/Steam/ubuntu12_32/reaper SteamLaunch AppId=2691235131 -- '/home/user/.local/share/Steam/steamapps/common/SteamLinuxRuntime_soldier'/_v2-entry-point --verb=waitforexitandrun -- '/home/user/.local/share/Steam/steamapps/common/Proton 7.0'/proton waitforexitandrun "/home/user/.local/share/Steam/steamapps/compatdata/2691235131/pfx/drive_c/Neople/DFO/NeopleLauncher.exe"", ProcID 96182
ThreadGetProcessExitCode: no such process 96353
ThreadGetProcessExitCode: no such process 96183
Uploaded AppInterfaceStats to Steam
(steam:89380): Gtk-WARNING **: 06:10:52.148: gtk_disable_setlocale() must be called before gtk_init()
(steam:89380): GLib-CRITICAL **: 06:10:52.148: unquote_string_inplace: assertion 'err == NULL || *err == NULL' failed
Replying to https://github.com/ValveSoftware/Proton/issues/5394#issuecomment-1047742417
Is your old account one linked with your Steam account or have you created in their website?
I am asking this because my account was created in Neople's website, which when opening the launcher it now forces you to have a Steam linked account. To solve this I created a dummy account with a spare e-mail, then click log-out and log-in with my Neople account, unfortunately I have to log-out and log-in every time I open the launcher.
This is an annoying workaround but this is a problem on their side. I couldn't find a way to link an existing account to my Steam account.
Edit: By the way, the game runs perfectly fine under Proton now, just don't change the resolution to "Windowed (free)" or you will have to manually change the config files to fix it.
@wizardlink Neople account. To be clear, I'm using the game downloaded from Neople's site added as a non-Steam game with Proton compatibility enabled.
I tried running the Steam version to the patcher at least to see if there were any different dlls listed in config_info, but it matched the one in my non-Steam added compatdata folder.
EDIT: Tried the above trick of logging out of a Steam account with the proper Steam version to log in to my Neople account. Same crash upon accepting the ToS popup...
@wizardlink Neople account. To be clear, I'm using the game downloaded from Neople's site added as a non-Steam game with Proton compatibility enabled. I tried running the Steam version to the patcher at least to see if there were any different dlls listed in config_info, but it matched the one in my non-Steam added compatdata folder.
EDIT: Tried the above trick of logging out of a Steam account with the proper Steam version to log in to my Neople account. Same crash upon accepting the ToS popup...
That's odd... I am trying to understand though, what do you mean with accepting the pop-up? When I open up DFO I only have a button on the top right of it to close it, I thought you meant that but got confused.
This is how it looks to me:

EDIT: I assume this is the pop-up you're talking about, since I don't have any other pop-up in the launcher unless I'm closing it.
@wizardlink Right, I should have included a screenshot. For context, this account has not been used once since 2019.
The Agree button becomes clickable once scrolled to the bottom of the ToS. Clicking it causes the patcher to immediately crash.
@wizardlink Right, I should have included a screenshot. For context, this account has not been used once since 2019.
The Agree button becomes clickable once scrolled to the bottom of the ToS. Clicking it causes the patcher to immediately crash.
Well, I give up. I have been trying on my free time to tackle this issue and potentially finding a solution, however there are a lot of edge case scenarios where your error falls in, the most common case I saw was due to a package mismatch in Ubuntu... But these reports are from 3-4y ago so they should not be a problem on LTS, if you even use Ubuntu.
I did not want to bother you about this since the Deck just launched, but @kisak-valve could you help us out with this edge case? I cannot reproduce it due to the fact that this popup only appears for returning players.
I did open an issue last week on WineHQ's bug tracker [link], since my crash is the same with Wine staging 7.2 as with Proton. The log from that has ieframe messages right before the backtrace that aren't in Proton's log.
Speaking of which, here's a proper Proton log of Steam's DFO launcher crashing from accepting the Terms of Service.
steam-495910.log
I did open an issue last week on WineHQ's bug tracker [link], since my crash is the same with Wine staging 7.2 as with Proton. The log from that has ieframe messages right before the backtrace that aren't in Proton's log.
Speaking of which, here's a proper Proton log of Steam's DFO launcher crashing from accepting the Terms of Service. steam-495910.log
I'm having the exact same issue as Don, same warning about a page fault, tried Proton 7.0-1, 7.0-3, GE 7-9 and GE 7-20, all crash upon accepting terms.
@DonKatsu I managed to fix this.
I installed steam+DFO in a windows VM, accepted terms of service and copied the files out of the vm, and it worked.
After 16/08/2022, the game disconnects after some minutes ingame, even if the connection is working properly. I suspect the culprit is the latest Nexon Game Security update, which doesn't seem to really like Proton. Weird, since the game ran perfectly before this update.
Similar to what @PirulicchioInfuocato said, I also have the issue of disconnect after some minutes ingame.
Heard it was due to proton's inability to handle DFO's heartbeat checks
proton 7.0-1x1 2022-06proton 7.0x1 2022-02proton experimentalx1 2021-12
Compatibility Report
System Information
I confirm:
steam-495910.log
Symptoms
Upon opening the game it complains that it doesn't has enough space, as seen here:

From what I have read, even after fixing the issue you still cannot press "Play" in the launcher as it's greyed out; I confirmed this by installing the game externally.
I must also add that the game supposedly (mixed messages across forums) has an anti-cheat, so it might not even be possible to be ran.
Reproduction