Well, have you tried breaking it up into simpler things you can do?
First you have a game board that's made up with hexagons and you have two different colors of pieces. As you say "simple". You can position the objects in C2's editor.
Second the players take turns moving one of their pieces on the board. Then if they land next to the opposite player's piece then the color changes.
That's basically the meat of it. So what can you do?
Can you come up with a way to move pieces?
This really depends on how you want to do it. Just look at the game and make a detailed step by step list of what you do and what is done.
Can you find opponent pieces close to the player's piece?
You could do it by measuring distance, detector sprites or even the overlapping at offset condition.
Can you make it turn based?
Basically just a global that's set to the current player and you make events to limit what pieces can be moved and such.