Change the system date to December 25th and start the game. Snow will appear, and some Darwinians will have Santa hats.
Map editor and mod player
Place "ModSystemEnabled = 1" in your preferences file of the root folder of Darwinia.Start up game and hit escape, there will be a new menu item called MODS.
Unlock All Areas
Create a new profile called "AccessAllAreas" or you can add the following line to your preferences.txt file: