Penumbra: Overture - Window gets messed up

[DanielSidhion]

Hello. I acquired Penumbra: Overture through the Indie Humble Bundle #2. When I launched it for the first time, my window got messed up, then I kept changing resolutions and it worked for the resolution 1280x960. However, now that I tried to open it again, the same thing happened, and no matter which resolution I select, the game won't open as full screen. Here are the details:

I launch the game through Steam, then a black screen with "Loading..." appears. After a while, the game reverses to the desktop, and I have to click its icon in order to make it appear in the screen. When I click the icon, the taskbar keeps in the screen.

I have a dual screen setup, am using Windows 7 64-bit and my taskbar is by default on the left side of the screen. The game didn't do that. The image on the right is the wallpaper. Here is an image to help:

http://img405.imageshack.us/img405/6171/72919077.jpg

I have looked the settings.cfg in Documents > Penumbra Overture > Episode1, and fullscreen is set to true.

In the other time I played with no problems, the taskbar didn't appear and the game was really "full screen" (not on both screens, only one).

What could be possibly causing this problem?

Thank you