https://github.com/spiffcode/hostile-takeover
I think this is most easy way to make a OpenRA mod based on existing game, becose This game has very C&C-like gamestyle.
To begin with, I would like to jointly understand how resource parsers work and how to adapt them for OpenRA engine, since I myself do not particularly understand programming code.
After that, it will be much easier to create other mods. and work on the subject
I do not set myself the task of making this particular mod with my own hand completely. If Anyone want to do something based of this idea, You are welcome.