Ok, got the game working (finally) by following Fusedcores (Steam Forums) steps outlined http://forums.steampowered.com/forums/showthread.php?t=2156747. I have left the Ark, the game runs smooth as butter, so far no tearing or lockups, textures look beautiful. Here's what I did step by step.

1. Uninstalled the game and video drivers completely. Rebooted.
2. Installed the latest production AMD drivers (11.9), then installed the Rage performance drivers. Rebooted.
3. Re-installed the game (Steam version. Thank god for fiber connections).
4. Created the rageconfig.cfg file (I used the one for high end systems) and placed it in the correct folder.
5. Verified all my graphics card settings are set to Application controlled.
6. Disabled Triple Buffering in the OPGL settings.
7. Started the game and it started up with no issue.

Initially I was getting the CTD at startup. That was fixed last night with the rage performance drivers. After which I could'nt get past the main menu (just got a black screen when starting a new game). Today I used Fusedcores custom config and the game started right up. looks pretty sweet too. On a side not, I don't run my system with a pagefile. Haven't used a page file since using Windows 7. I hope this helps. Below are my specs.

Win7 Ultimate 64bit
Intel Core2 Quad, Q8200 @ 2.33GHz
8 GB RAM
XFX HD 6850, 1GB
1TB WD Black Series SATA HD

Update: After playing for approximately 2 hours, I have had no problems with the exception of texture pop in that progressively got worse the longer I played. But that was resolved by exiting the game and restarting when it got bad enough to be annoying. Other than that, the game runs smooth without any lag or stutter.

I tried all your steps and still get errors after the intro.....

Here is my spec

Win 7 32bit
i7 920
x58
ATI HD 5850
I have not tried the case without pagefiles. Maybe I should give it a shot.

How much system RAM do you have?

Oh I did not mention that...lol

4G, which is sufficient in a 32bit system. I can only run the game after using Skidrow's crack patch ( I brought this game) and errors still happen quite frequently.

By the way thanks for sharing.