Black floor, see through doors, and other problems

[jashen]

I downloaded the very FIRST penumbra, the free one that has the flying monsters, when i downloaded it, it said *It may of not installed correctly* but i redownloaded it just about 30 times, at the start i can move around and interact with things, but the floor is black, and it doesnt tell me the names of my items, and the doors are see through and so are some walls, i have the latest patch / version im running a HP Pavilion dm4 and i have windows 7