So since this is a miscellaneous file I will give my opinions as five different categories.
Playability: Well there isn't much to do but siege the AI's castles (should be easy because all economy is already set up in the player's advantage). I guess this map should be better described as eyecandy. (3)
Balance: The player is given an obvious advantage over the enemy AIs, so winning is really easy. (2.5)
Creativity: A massive castle that stretches from east to west. Even the terrain shapes its design. This kind of gameplay (building your own castle on a skirmish map) is rare. (5)
Map Design: Making a skirmish map from scratch just for this castle is very impressive. From the minimap, the island looks natural; from actually playing the mission, incredible. (5)
Story/Instructions: It's a good story, and I liked how you put it together with the screens in an image. (4.5)