Okay, so I've read about a bunch of lighting issues, but after 5 days of scouring the threads on here, I have yet to find a fix to the problem I'm having.
It began with my realization that the game being upside-down was not, in fact, supposed to happen. I fixed that problem, but now there seems to be a remnant of the previous lighting issues left over. Here's some screenshots and a video of what it looks like:
http://img827.imageshack.us/i/dscf0725.jpg/
http://img705.imageshack.us/i/dscf0726b.jpg/
http://img863.imageshack.us/i/th2v.mp4/
Apologies for the crappy quality, I couldn't get in-game screenshots to work, so I just used a camera X(
Anyways, it's like the light effects are still stuck in upside-down mode. I've updated my video drivers (rebooting in between uninstalling and installing new ones, which fixed the initial upside-down problem), reinstalled the game, tried turning on and off all effects, and setting all settings to high and low, restarting when needed. Nothing has worked so far. Here's my specs, and hpl log is attached.
OS: Windows Vista Home Premium SP2 (64-bit)
Processor: 2.4 GHz Intel Core 2 Duo
Memory: 4GB
Video Card: ATI Mobility Radeon HD 3650