Test project C#, Unity
Controls:
// In Game
[W] [A] [S] [D] to move camera
Hold [Right Mouse Button] to look around
Click on unit to select it
Click on unit holding [Shift] to add unit to the selection
Click on land to send selected units
Hold [Left Mouse Button] to select several units
Scroll Mouse Wheel to zoom in and out
Drag and drop castle to build one
Screenshots: