I just downloaded Amnesia from the Frictional site and am having the same problems. I'm running Intel but it's updated to the current version and, at least with what I can see, should be able to function fine. Any thoughts on what the probem is? I can see the menu and subtitles but the gameplay is just a black screen. Here's my HPL:
Initializing Graphics Module
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Init lowlevel graphics: 1024x768 bpp:32 fs:1 ms:0 gpufmt:2 cap:'Amnesia - The Dark Descent - Loading...' pos
-1x-1)
Setting video mode: 1024 x 768 - 32 bpp
Init Glew...OK
Setting up OpenGL
Vendor: Intel
Renderer: Intel® HD Graphics
Version: 2.1.0 - Build 8.15.10.2342
Max texture image units: 16
Max texture coord units: 8
Max user clip planes: 6
Two sided stencil: 1
Vertex Buffer Object: 1
Anisotropic filtering: 1
Max Anisotropic degree: 16
Multisampling: 1
Texture compression: 1
Texture compression S3TC: 1
Auto generate MipMaps: 1
Render to texture: 1
Max draw buffers: 8
Max color render targets: 8
Packed depth-stencil: 1
Texture float: 1
GLSL Version: 1.20 - Intel Build 8.15.10.2342
ShaderModel 2: 1
ShaderModel 3: 1
ShaderModel 4: 0
OGL ATIFragmentShader: 0
ATTENTION: System does not support const arrays in glsl!
Setting up G-Bugger: type: 0 texturenum: 3
Adding engine materials
Initializing DevIL
Vendor String: Abysmal Software
Version String: Developer's Image Library (DevIL) 1.6.8pre Aug 12 2006
Version Number: 168
Adding engine post effects
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