I've tried this on both the original game and on Justine,
When I get to an item (the tinderbox in the room next to where Daniel wakes up in Amnesia, and the lantern in Justine), the game freezes.
The audio continues for a couple of seconds, then cuts off.
I'm playing on all low settings, turned everything off, tried various resolutions, no help.
I'm using a Nvidia GeForce 6150SE nForce 430, and I've heard this game can be very particular over which graphics card is being used...
All the Penumbra games work flawlessly
Also, thank you