These External Tools maybe helpful to you:
Pattern Maker Crossbowman has made a pre-release editor that can take a picture and make a map based on the picture you draw in a bitmap file.
Composite Editor zapdotep's editor used to edit DRS and DAT files. Mainly used for creating scenarios which include many of the hidden objects that are not normally available when using the standard scenario editor that comes with the game.
Composite Editor Source Code zapdotep is cool like that, he released his editor as open source. Please when using this source code leave the original Author credit.
Extract Scenarios from Campaign Files
Lloyd Kinsella made this program to extract the scenarios that are bundled with the campaign files.
Artificial Intelligence Editing Stoyan Ratchev created this little program to help create an AI file. The tool is handy for those seeking to create custom or pop 200 AI's.
Personality Editor This tool helps change the personality of the computer players. This is Martin Sturm's Per Edit
City Plan Editor This tool helps define where the computer player builds. It had some bugs but it seems to work for most things, it's just not perfect or exact.
DAT File Excel Sheets Rasteve's Excel sheets that describe the data in the DAT files
DAT File Editor Used to change Unit and Building stats. scenario_t_c is the original author of the program.
Advanced Genie Editor Keisari Tapsa has made a tool that can be used to edit the graphics of the game.
Graphics Compiler and Decompiler Ruralist has designed a nice compiler and de-compiler used to get access to the graphics you want to edit.
Pebble32 Editor Originally made by Localization Tools Group (no defunct) and posted by The Dark Archer for public download. It is used for Language DLL editing.
Editing the Language DLL Tutorial Written by The Dark Archer.