Changelog for patch #12 /GOG-3 (Windows and Linux) / GOG-1 (Mac) (added 04.09.2015):

New content:
- Daily challenge: On this mode, you'll face a new challenge each day, with the same starting conditions and dungeons for everyone. You'll only get a single attempt each day, so be careful! (Windows + Mac)
- New boss: Brunilda, Carrot Princess, is a new boss that can appear on Floor 4.
- New enemies: Yellow Chili and Green Pepper.
- New playable characters: Carina (female Apprentice), Loki (Vagabond), Glyndor (Battlemage), Agnes (Witch), Leto (Cleric)
- 10 New perks
- New combat modifiers and divine rewards.
- New room layouts
- New room goal: On Scavenge rooms you need to pick up magic crystals while avoiding incoming fire.
- Added Brazilian Portuguese language

Improvements and fixes:
- You can switch weapons when they reach half their cooldown time.
- Fixed minor exploit with the sprint function
- Fixed default FOV being too low
- Fixed a minor weapon switch bug
- Fixed damage source direction being wrong
- Balancing: Nerfed Bone Summoners a bit.

Looks like a great update with lots of content, but the game crashes on launch for me now. Windows 7 system, previous version was running fine.

Debug output if it helps:

Problem signature:
Problem Event Name: BEX
Application Name: Ziggurat.exe
Application Version: 4.6.6.2872
Application Timestamp: 55757248
Fault Module Name: MSVCR110.dll
Fault Module Version: 11.0.51106.1
Fault Module Timestamp: 5098858e
Exception Offset: 0009f979
Exception Code: c0000417
Exception Data: 00000000
OS Version: 6.1.7601.2.1.0.768.3
Locale ID: 1033

I had the same Problem, old version runs new version crashes, until i deleted the Galaxy.dll in the gamefolder.

Are you using GOG Galaxy? The game uses different code paths depending on that. Removing the Galaxy.dll file causes the game to run on the platform agnostic code path (no leaderboards, achievements or daily challenges).

Anyway, the log file would be useful. It's located on the Ziggurat_Data folder.

Galaxy is installed but not running.
Game starts -> black screen ->CTD -> Microsoft Visuall C++ Runtime Error

Have you told your firewall to allow the game access to the localhost? This is usually 127.0.0.1. I've noticed that Galaxy games need access to this, and sometimes they need access to the whole internet to launch properly.

Usually Windows pops up a dialog asking if I want to allow the program access through the firewall. However, as this in an update of my previous installation, I probably denied it last time and thus it just crashes out. I'll try removing the Galaxy DLL fire (well, renaming it), and if that doesn't work I'll check the firewall entries. Thanks everyone for the feedback!

That did it. Renaming the Galaxy.dll to something like Galaxy.dll.offline enabled me to run the game just fine.

Optional client indeed.

Thanks for the log file, were those the whole contents of it? It doesn't show any error or unusual behavior, so it could be the Galaxy DLL itself crashing, and not the game.

With the Galaxy.dll inside the folder it really is the whole content, the errors only show up in the log when i delete the dll.
And i'm totally with you and say it has nothing to do with the game itself.
Maybe its due to an outdated version of Galaxy on my system that causes the problem, but even after uninstalling the Galaxy Client the game won't run with the dll.

Thank you, those errors are indeed expected if you have deleted the Galaxy DLL.

I don't know if there's a way to debug the Galaxy DLL so I'm afraid I can't be of more help :\

Well this is kind of a mixed bag.
The Good news is the game runs now without any problems after i searched the registry for Galaxy and
deleted the 4 entrys "Galaxy Client" "Galaxy Client Communication".
The bad news is before uninstalling Galaxy a few days ago i did not save the logs nor did i look up what version i was running.
So the only information i have left is, that the Client was from the time when The Witcher 3 launched.