When editing the DLL files it is important to take into account the palettes of each gif. Some gifs use the
nornal Civ2 pallete while others deviate. If you keep your new graphics in the same color palette as the
gif to be replaced there should be no problem. As always, test before you publish.
DLL Civ2 Regular Palette?
Tiles Yes *** Do not deviate on size for the Report Screens
MK No *** Do not deviate on size for the Conquer and Diplomacy graphics
SS No *** SS Parts can be overlayed and expanded within the actual gif limits
PV No *** Throne Room Additions can be overlayed and expanded within the actual gif limits
CV No *** Do not deviate on size for the City View graphics
Notes:
Civ2 DLL files are located in the Civ2 directory
All sizes are in pixels
The Separate Graphics Column is if there is more than one graphic within the file
Use Gif Xtractor Beta 3 to unlock the gifs from the DLL files and then save them back in the file.
Use Paint Shop Pro to get accurate palette renderings
Use the official Civ2 palette from the Scenario League -----> http://sleague.apolyton.net/Guides/sldt_palette.shtml
ALWAYS BACKUP YOUR DLL FILES! mess up and you'll have to reload!  
This handbook was created by Harry Tuttle 5/15/2004
Thanks to Boco for bringing this up.