Penumbra: Black Plague, NEED HELP!

[jssi03]

I just hope someone can figure it out and do something about it cause I am all out of ideas. I actaully tried starting over and loading different saves and defragmenting and all that stuff even using Steam's defrag on it and useing the varification tool as well and still no change. I also have it for Steam. Maybe it is just Steam? They messed something up when they put it on thier servers? Who knows but until it is solved I will never actually beat BP by myself. I had to go and search and search for the ending from that exact point on to see what happens.