So, I've been Googling for a while now, and have yet to find a solution for this issue.

I have the Steam version of the game, and during cutscenes I notice a lot of flickering in the textures that seems to go away when gameplay resumes. However, in Foltest's camp (right outside Geralt's tent, to be specific) the entire map will suddenly flash white. This is a very distracting problem, and I'm worried it will continue throughout the rest of the game. Has anyone else had this issue? Is there a known fix?

My specs:
Intel i5-4670k (Stock speeds)
Gigabyte GeForce GTX 770 (Driver Version: 344.75)
8GB of RAM

I did make some changes to my user.ini file and set it to read-only. Apparently the games configuration tool doesn't always add all of the variables?

My user.ini Rendering Section:
[Rendering]
AllowAntialias=1
AllowBloom=1
AllowBlur=1
AllowCutsceneDOF=0
AllowDOF=1
AllowDecals=1.0
AllowMotionBlur=1
AllowRain=1
AllowSSAO=1
AllowScatterDOF=0
AllowShafts=1
AllowSharpen=1
AllowVignette=1
AspectRatio=0
AtlasTextureDownscale=0
CharacerLodGameplayDownscale=0
DanglesLimiter=0
DetailTextureDownscale=0
Fullscreen=1
FoliageDistanceScale=1.0
MaxAtlasTextureSize=4096
MaxCubeShadowCount=3
MaxCubeShadowSize=2048
MaxSpotShadowCount=3
MaxSpotShadowSize=2048
MaxTextureSize=2048
MeshDistanceScale=1.0
ShadowQuality=3
ShadowedLights=3
TextureDownscale=0
TextureMemoryBudget=400
TextureTimeBudget=10
UberSampling=0
VSync=0

Please note that I was experiencing the aforementioned issues before changing the ini. If there are some settings that need to be changed, I'm happy to do so, but my changes do not seem to be the cause of the problem.

Thanks in advance for your help, and I hope that someone can provide some more information about this problem.

Try disabling Cinematic Depth of Field in the Launcher (=> Options => Advanced Options) or better disable all DoF options (according to your User.ini Cinematic DoF is already disabled).

SSAO can also be a performance killer as well as ubersampling.
Check what happens when V-Sync is enabled and disabled on your system.

Further, don't force anti-aliasing and anisotropic filtering in the graphics card’s control panel.

Some people get much better performance by using this fix:
http://www.moddb.com/games/the-witcher-2-assassins-of-kings/downloads/witcher-2-stuttering-fix
It fixes stuttering caused by the game rendering too fast on powerful machines.

On other machines, the flickering in cutscenes happens because of very high resolutions. While the game still runs fine, cutscenes seem to be less optimized and start causing performance issues then.

That's because you set these two variables to minimum

FoliageDistanceScale=1.0
MeshDistanceScale=1.0

You can try to change them like this

MeshDistanceScale=1000
FoliageDistanceScale=1000

edit: also, did you edit the right user.ini file? For Steam version it should be Users\Username\Documents\Witcher 2\config\user.ini

NOT Steam\steamapps\common\the witcher 2\bin\config\user.ini

Yes, I edited the right one.

I really don't know what it is with the game. I'm in Flotsam, and the white flashing has gotten worse than ever, especially in the village right outside the walls. I'm not sure how to describe it; it's almost as if the textures are suddenly disappearing, leaving just a gray/white model.

Add to that the fact that the game has taken to crashing. So far I've gotten one CTD and one lock up, both within about three hours of each other.

My Google searches for this white flashing have been for naught. Has anyone experienced this is any other games?

I've given this another thought. The game's engine uses multiple 2D sprites for all objects unless you get close. Then they are replaced by 3D models. Your issue seems to be connected to the 2D representation, so maybe it's a driver issue (check for updates) or maybe DirectX isn't working as expected.
Make sure it's properly installed on your system, by (re-)installing the DirectX End-User Runtimes (June 2010)
http://www.microsoft.com/en-us/download/details.aspx?id=8109
Run and extract the file to a separate folder, then start DXSETUP.EXE for installation.
Afterwards run the DirectX Web installer for newer components and updates:
http://www.microsoft.com/en-us/download/details.aspx?id=35

Hi i have the same problem and i dont know what's causing it. Other games like bf4,Thief, Far cry 4 run fine. I have Gigabyte Gtx 780 Ghz ,I7 4770k and 8gb of ram.