If it can be of any help:
error.txt file: http://pastebin.com/yWvmtAqP
output_log.txt file: http://pastebin.com/DAd7fkaC
report.ini file: http://pastebin.com/WVgGWXDS
Here is the stracktrace of the core:
Seems there is some kind of problem with the Steam API when the CloseCharacterCreation method is called.
========== OUTPUTING STACK TRACE ==================
(0x5DDA5D99) (CSteamworks): (filename not available): ISteamUserStats_SetAchievement + 0x9
(0x1A81FD19) (Mono JIT code): (filename not available): (wrapper managed-to-native) Steamworks.NativeMethods:ISteamUserStats_SetAchievement (string) + 0x61 (1A81FCB8 1A81FD7A) [05D24E70 - Unity Root Domain] + 0x0
(0x1A81FBE6) (Mono JIT code): (filename not available): Steamworks.SteamUserStats:SetAchievement (string) + 0x16 (1A81FBD0 1A81FBEB) [05D24E70 - Unity Root Domain] + 0x0
(0x1A81FBAC) (Mono JIT code): (filename not available): SteamManager:SetAchievement (string) + 0x34 (1A81FB78 1A81FBB6) [05D24E70 - Unity Root Domain] + 0x0
(0x19A007FC) (Mono JIT code): (filename not available): AchievementTracker:CheckAchievement (AchievementTracker/Achievement) + 0xbc (19A00740 19A00831) [05D24E70 - Unity Root Domain] + 0x0
(0x19A0070F) (Mono JIT code): (filename not available): AchievementTracker:CheckAchievementRequirements () + 0x3f (19A006D0 19A0072E) [05D24E70 - Unity Root Domain] + 0x0
(0x1A81FB52) (Mono JIT code): (filename not available): AchievementTracker:IncrementTrackedStat (AchievementTracker/TrackedAchievementStat) + 0x2a (1A81FB28 1A81FB77) [05D24E70 - Unity Root Domain] + 0x0
(0x1A81EA18) (Mono JIT code): (filename not available): UICharacterCreationManager:CloseCharacterCreation () + 0xf20 (1A81DAF8 1A81EEDB) [05D24E70 - Unity Root Domain] + 0x0
(0x1993D83D) (Mono JIT code): (filename not available): FadeManager/<SignalOnFadeEndAfterFrameDelay>c__Iterator4D:MoveNext () + 0x7d (1993D7C0 1993D856) [05D24E70 - Unity Root Domain] + 0x0
(0x0636A3B1) (Mono JIT code): (filename not available): (wrapper runtime-invoke) <Module>:runtime_invoke_bool__this__ (object,intptr,intptr,intptr) + 0x41 (0636A370 0636A41A) [05D24E70 - Unity Root Domain] + 0x0
(0x100F037C) (mono): (filename not available): mono_set_defaults + 0x22cb
(0x1005D7C3) (mono): (filename not available): mono_runtime_invoke + 0x51
(0x00FB43A8) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x28928
(0x01051635) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0xc5bb5
(0x010517BE) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0xc5d3e
(0x010515E1) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0xc5b61
(0x00FA420D) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x1878d
(0x00FA4443) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x189c3
(0x00F8D59E) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x1b1e
(0x0101E757) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x92cd7
(0x0109519B) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x10971b
(0x01096C85) (PillarsOfEternity): (filename not available): Behaviour::Transfer<StreamedBinaryRead<1> > + 0x10b205
(0x0130CEC8) (PillarsOfEternity): (filename not available): AnimationEvent::Transfer<StreamedBinaryRead<1> > + 0x123b58
(0x01341DB0) (PillarsOfEternity): (filename not available): AnimationEvent::Transfer<StreamedBinaryRead<1> > + 0x158a40
(0x752D7C04) (KERNEL32): (filename not available): BaseThreadInitThunk + 0x24
(0x7708B54F) (ntdll): (filename not available): RtlInitializeExceptionChain + 0x8f
(0x7708B51A) (ntdll): (filename not available): RtlInitializeExceptionChain + 0x5a
========== END OF STACKTRACE ===========
**** Crash! ****
The issue is 100% reproductible. However the game doesn't crash if I don't launch the game through Steam (directly launching the binary from its folder). But if I don't want to launch the game without Steam behind. If I bought this game on Steam, it is to benefit from its features: achievements, steam cloud, community sharing...