I have v2.21 and I would like to start adding all of these customized units. The editors that are available do not work with latest version of civ3. I have changed the pedia stuff and put the files in the correct directory. What do I do now? TIA

The Hacked 1.21f Editor (http://www.civfanatics.net/uploads/Civ3Edit.zip) works with the newest patch to add units.

Also see this tutorial (http://forums.civfanatics.com/showthread.php?s=&threadid=9337) to learn how to add units properly without the game crashing.