There is no digital signature for the Mac download version. It has not changed from the file served prior to 21 April. Exact same hash. Tried 21 April, 22 April, and 11 May.

Has no one else noticed this?

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Changelog for update (added 16 June 2017):

- added The Art of Cyan Digital Book for qualified Kickstarter backers.

Changelog for Patch 1.6.1 (added 25 October 2017):

- Unreal Engine updated to 4.15.3

General
- Lightmap data size on disk dramatically reduced
- Game-wide Texture resolution optimizations
- Better-tuned scalability settings
- Arai creature optimized to reduce hitching
- CW updated to use less resources
- Book system optimized to reduce hitching
- Loading screens now display progress
- Level streaming optimizations
- Startup videos added
- UI navigation fixes

VR Features & Fixes
- VR support no longer requires VR command line flags
- Wearing or removing VR headset will enable or disable VR automagically
- New and improved hand models for VR motion controllers
- Fixed teleport position issue when attempting to teleport to an invalid location first
- Fix for threading issue that could occur if motion controllers disconnect
- License plates have been enlarged in VR mode for better readability
- VR controller interface updated to support various motion controllers
- Teleport indicator provides a better sense of depth
- Subtitles improved to reduce penetration with other objects in the scene
- Interaction with in game devices improved for motion controllers
- Better Vive support
- Player height fixes
- Added support for stereo capture cameras to clean up portals
- Show tracking sensors (if controller connection lost) to help players reorient

Media Player Features & Fixes
- New media player framework
- Increased stability of media player
- Movies now loaded only when needed
- Increased trigger area for Farley’s message in Maray
- Fixed issue with imagers still playing audio & video when disabled
- Removed test movies that are no longer needed

Razer Chroma Updates
- Updated Chroma to support new hardware, including Chroma Link.
- “Breathe” animation deprecated by Razer - ambient world color is now static gradient

Audio Features & Fixes
- Ensure arai swarm audio components do not auto-activate
- Don’t use Oculus Rift audio device for startup movies if Rift isn’t connected
- Fix for a threading issue when ambient sounds are removed
- Subtitle loading is now asynchronous
- Music player music loading is now asynchronous
- Music and dialogue can be marked to play when volume is all the way down
- Fixed audio hitching on devices that put resources on the game thread

Localization
- All [Simplified] Chinese texts have been reviewed for accuracy and are now complete
- Any menu terms that were not localized are now complete
- Minor corrections made to the Portuguese language
- Overlapping menu texts have been fixed
- Cut-off menu texts have been fixed
- Missing menu texts for localized languages have been added

Changelog for patch 1.6.4 (added 30 October 2017):

General fixes:

- The Windows 7 DXGI error should no longer appear on affected systems

Global VR fixes:

- The resolution scale will now stay put when playing in VR
- Fixed the issue with VR headsets not properly switching audio between the HMD and system speakers
- Player shadow should no longer appear when driving the Minecart
- Fix for Mouse Cursor Locked Toggle
- Will only use the VR audio device for media player if force VR is used.
- Fix for the hands being in the wrong location while in the minecart.

Vive fixes:

- Free roam should now work when you disable the Vive wands.
- Fix for missing loading screen on vive while in Minecart
- Improvements for quickly swapping between Vive and desktop modes

Graphics setting fixes:

- View distance options are no longer offset by one position.

Changelog for Patch 1.6.5 (added 08 November 2017):

General fixes:
- Fix to spawn actor performance

Oculus Fix:
- Touch control updates

Changelog for Update (added 03 January 2018):

- Updated the game's manual to version 1.6.5.

Changelog for Patch 1.7.1 (added 15 March 2018):

We're constantly tweaking and fixing Obduction, but this update has a bit more than just tweaks and fixes.
- We've included a few extra places to explore -- places that fill in a bit more of the story.
It's a perfect time to play Obduction again, get a bit further, or maybe even try Obduction in VR. Make it home.

Changelog for Patch 1.8.0 (added 02 August 2019):

New to Obduction:
- UE4 upgrade to 4.21.2
- New saved game path location for Mac users - this change is being handled by the UE4 engine and not Apple's macOS (*see additional notes below). Save games and config files are now stored in: library/applicationsupport/epic/obduction
- Performance improvements
- VR Improvements:
- Ability to backstep while using VR teleport
- Index and Index Controller support added
- Windows Mixed Reality (via SteamVR) support added
- Turkish [fan] localization added

Known Issues:
- In some circumstances the game may require a restart in order to apply graphics quality settings changes. e.g. If you have ‘Low’ settings applied at launch and change them to ‘Epic’ the game will require a restart in order to apply the changes
- When using a SteamVR device (Vive, Windows Mixed Reality, etc) the first time a user enters the minecart they may find themselves facing backwards. We’ve attempted a fix for it, but it caused more problems than it solved. User should be able to turn in the minecart and face forward with no issues.

Windows Mixed Reality headsets:
- A crash can occur if the headset is unplugged, fully powered off, etc. during gameplay
- Under some conditions with certain WMR headsets, the laser pointer will not take effect on the main menu, forcing the user to point with the headset and select the menu entry with the main button on the wand. Once in game, the input will correct itself.
- Ambient occlusion differences in each eye visible in some areas:
- Under some conditions, a difference in shadows and lighting can be noticed in each eye in some VR headsets.
- Mac OS Catalina (beta) may exhibit unusually long pauses and stuttering video playback.
- *MacOS Users: Due to changes in how and where save files are written to disk, once the game has been run after receiving the update, your save files will no longer be available in an older release. Users who choose to roll back to the previous release will need to manually move the files back to the original save location. Your original save file location can differ between two locations depending on OS release and when the directory was created: ~/Library/Containers/com.cyan.obduction/Data/Library/Application Support/Epic/Obduction/Saved/SaveGames or ~/Library/Application Support/Epic/Obduction/SaveGames

Changelog (from Steam) for Patch 1.8.1 (added 12 August 2019):

Improvements made:
- Fixed issue that caused you to strafe and turn in VR Free Move mode.
- Fixed the large stone stair sphere in Hunrath. It now rotates as expected.
- Controller note: In Teleportation mode, both left and right controllers can be used for turning. In Free Move mode, only the right controller will turn.

Known issues:
- If you run into an issue where you cannot move, you need to delete your Input.ini file and run the game again. This file is located at...
Windows: %LocalAppData%\Obduction\Saved\Config\WindowsNoEditor
Mac: ~/Library/Preferences/Obduction/MacNoEditor (Use Command+G to type in the path.)

- When using smooth motion input with Windows Mixed Reality motion controls, a movement ‘drift’ can occur. We’ve found this is a common problem. If this happens, open up the SteamVR Input configuration for Obduction and add a dead zone to the left joystick “move” input.

Changelog for Patch 1.8.3 (added 03 October 2019):

- Fixed fog and Cloud appearance
- Fixes for object manipulation
- Added controller bindings for VIVE Cosmos

Changelog for Patch 1.8.4 / GOG-32920 (Windows) (added 04 October 2019):

- Fixed being forced to teleport navigation in VR while in game.
- Fixed menu becoming unresponsive when switching between VR/2D.

Patch 1.8.4.1 (07 November 2019)

Hey all,

We've pushed out a small update today to address the issues that were being caused by HDR. After quite a bit of discussion, looking at our options, and finding out what we could do with the small amount of time and resources we have, we've come to the conclusion that we'll have to disable support for HDR for the time being. We'll post an update with news if or when we're able to revisit this issue.

Thanks everyone.

Patch 1.8.4.1-SSL (29 November 2021)

Fixed crash on startup on some machines, like 11th gen intel machines. Very specific, we know! It has to do with an SSL library thing that Intel doesn't have pre-installed that causes issues with startup on Obduction.