TEXTURES
The simplest mod you can make is simply changing the textures in the game. Here is what you need to do:
1 - Choosing
All of the objects in AMRTS have textures, and some, like the hq, have more than one. To edit the textures, go to your extracted base.x and find one to edit. The ones for units and buildings are in:
objects > army > art
objects > army > art
2 - Edit
Now you have picked a texture, you can change it to be whatever you like. As long as the image is the same size and name as the original, it will work.
3 - Installing
By now you should know where to put the files. If not, then you have to go into your 3DO Army Men RTS folder, in base, then in objects, army, art. If any of them don't exist, you will have to make them.
4 - Testing
Load up AMRTS, if you get any errors, make sure you saved the texture as TGA and turn off any RLA compression options. Make sure it is saved correctly, e.g. the correct name.
If all works, you should end up with something like this:
If all works, you should end up with something like this: