How to make map zones change color instead of using control marker

Take Axis and Allies for example. Instead of placing a German control marker in a Soviet territory after taking it I would like to create a right click menu option to allow you to change the territory from red color to grey. This would look much nicer than placing markers. And would mimic how territory color changes in computer games of this sort.

I actually want to do this in the Black Swan module I made. Perhaps there are good examples out there already that do this. Can someone point me to a few module examples to learn from?

I don’t have an example module for you, but here’s the reference manual page explaining how to do this with zones: Multi-Zoned Grid. In particular, you’ll want the Use Highlighting option and a pair of Zone Highlighters.