Does the Capital tile act the same as a city tile? Does the person who places it put their cube on it and does it score the same as a city tile? I only ask because there isn't a cube silhouette like the city tiles.
The capital city tile acts like every other city for all intents and purposes. So the player will put their color cube on it to show ownership and all abilities referring to cities would be triggered. The one difference and the reason why it has a special color tile is end-game scoring. It receives a point for all adjacent ocean (in addition to adjacent greenery), so you need the white tile to show which city you built is the capital.