Also posted at How to make Thief 2 run on a modern computer
The advice given at the above thread and at http://www.johnanthonycurran.com/gamemods.html#thief
worked spendidly for me when re-installing T2 on a new machine (64 bit Vista with 4 processors). The only "trouble" I had was with DDFIX; I had to manually hex edit Thief.exe to get it hooked up. Not hard, once I downloaded a hex editor for Vista, but it would have been nice if the GUI installer had worked. But what a difference in the graphics with DDFIX! The hex editor that I found & liked was: Hex Editor Neo
Also of note, GarrettLoader installed and works just fine with no mods in Vista. I also like how GarrettLoader now points you to the right places to download FM scripts now. I don't remember that from before. Thanks!
The steps I followed:
1) I did a clean install from the newest copy of Thief 2 that I have from SoldOut Software. I just bought it this year at Amazon (it has both T1 and T2 on it) as a backup for my older copy (also from SoldOut). This CD claimed to be Vista Compatible. It did install with no problems, but Thief did not run cleanly and locked up.
2) My version was up to date, so no need to patch. I used imagecfg after backing up my exe. That worked well enough to let me run the program, but the graphics were horrible.
3) Since I have 2 NVIDIA GeForce 8800 cards, I was expecting great graphics. Editing USER.CFG to un-comment (remove semicolon) from the ";safe_texture_manager" line made things better, but still not great.
4) I then decided to try the Thief 2 patched exe from John Curran's site. I backed up my exe again, and switched in the moded version. It worked. Hard to tell if it fixed anything I had not already fixed. But it works fine.
5) Next, I went to Timeslip's DDFIX webpage and picked up the GUI version. I read the readme file included in the zip file (I used 7-zip to expand the .7z file, though I suppose WinRar should work also). Unfortunately, the GUI did not work. Either it is not Vista compatible or not multi-core compatible or something else. In any event I then followed the Manual installation instructions and had no further problems. This is what my DDFIX.ini looks like after my edits:
;Must be 800x600 or greater
;Refresh rate. 0 is default, anything else to override.
;Set to 1 to fix the duel core related crash
;Set to 1 to automatically register lgvid.ax each time thief is started up
;This can be set to zero to get a more accurate z-buffer
;Doesn't usually make a noticable difference to picture quality
;Turns on the 32 bit texture loader and adds support for some unsupported screen resolutions
;Will cause a crash if used with an unsupported exe
; 0 - Disable
; 1 - Determine exe automatically
; 2 - Thief 2 v1.18
;Set to 1 to disable the windows keys while thief is running
;Set to 1 to enable anisotropic filtering
;If you want to share overriden textures between thief installations, uncomment the next line
;It should contain the absolute path to the equivilent of \res\ddfix, including the trailing \
;XX Compatibility settings XX
;Changes the way direct writes to the frontbuffer are handled
;SS2 players should set these options to '2' and '0xf81f' respectively
;Thief 2 players with corrupted in game text should use '2' and '0x0000'
;Players who experience slowdown with UseSysMemOverlay=2 should set both options to 0
I then edited cam.cfg to have the same screen resolution as DDFIX.ini. With all this done, my graphics were looking good, but no movies!
6) Finally I installed the updated Indeo codec (version 5.11). The weekend I did all this, both ttlg and Thief-thecircle were down. so I googled it, found the updated codec and installed it. To tell the truth, I don't recall which site I used to download it from. There are several. The one I chose claimed to be certified virus free, and seemed to be telling the truth.
That's it. Now all I need to do is pick up the enhanced texture pack I remember being released earlier this year or late last.
I could not have done it without the great advice by Peter Smith and John Anthony Curran. Thanks!