Slow game and black screen

[Zhadius]

Well, hi.
I'm facing 2 different problems: Slow game and black screen, at different times of curse.
First, about my machine: It's an ASUS A42F.
GPU driver up to date.
Now, the slow game:
Well, it's kinda strange because I've tried in low settings 800x600 and high settings 1366x768 and the game runs at the same speed on both. I'm not sure why this happens.

And the black screen:
I'm in the begging of the game, really.

Spoiler below!

From the entrance hall I go to the Archives and there's a room there where you find a letter, actually there are 3 rooms like this i guess, but it's the last one, the one that you fall after getting the letter, then the screen fades and you listen the guy telling the story.

But after that the screen continues black, and there's nothing I can do, so I'm kinda stuck o.o

Thank you for the attention! =)