DrearierSpider: I may be the first taffer in history with this complaint, but my the game is actually too bright for me, and using the in-game gamma slider does not do a thing. The game was installed using version 2.0.0.18 installer (the most current one at time of posting), and patched to NewDark 1.21 using TafferPatcher, with the visual enhancements and level fixes. Using Windows 7 64 Bit, Intel HD Graphics card.
Try the following:
1. Open cam_ext.cfg from the main Thief 2 directory with Notepad. As always when editing .cfg files, you may want to make a backup of the file before editing it.
2. At the top there should be a section labeled "display mode". Make sure that the option "use_d3d_display" is enabled (i.e. it doesn't have a semicolon in front of it).
3. Scroll down to the section labeled "D3D9 render options", about halfway down the file. Remove the semicolon in front of the first option listed here, "d3d_disp_no_rgb10_buf".
4. Save.
You should now be able to adjust the gamma with the in-game menu.
Edit: Oops. Oh well, better late than never, I suppose.