Well after repeatedly fighting with the XP versions of SMAC that have been around for a while, I was hoping GOG's version would work, but I got the same crash and error as always, same as you guys.
However, today I was finally able to get back to the good old days and got it to run! I don't know which combination of the steps I took resulted in the fix, but this is what I did:
First, I did some much needed updates anyway as per the "common troubleshooting steps" outlined here:
http://www.gog.com/en/support/sid_meiers_alpha_centauri/_i_b_read_first_b_common_troubleshooting_steps_i_ ...including updating XP with windows fixes and updating my NVidia GeForce Go 7900 GS card with a new driver. I also dl'd the DirectX package that they recommended.
Now, after this it still wasn't working, so now I started fiddling with SMAC itself:
Step1) Tried various compatibility modes. Eventually one of them (I think it was setting screen resolution to 640x480 and running in 256 colors) went at least far enough in the SMAC initialization to create the factions txt files etc, and in particular the AlphaCentauri.ini file.
Step 2) Trying a random suggestion from a loosely related post at the civfanatics forum (
http://forums.civfanatics.com/showthread.php?t=367858) I made sure the following was in the newly created AlphaCentauri.ini file:
[Alpha Centauri]
ForceOldVoxelAlgorithm=1
DisableOpeningMovie=1
DirectDraw=0
Step 3) run SMAC! In the end I didn't need to have any compatibility boxes selected.
I guess it may be an issue with the opening movie playing, though I just played through and didn't have any other issues with graphics or the project completion movies or anything so I'm not sure why the opening movie would cause the error (if the magic line that I added is that line and not the DirectDraw line, but its working now so I'm not touching nothing to figure out which line is the important one!)
Hope this helps at least some people out there! Happy gaming!