All areas unlocked:

Enter AccessAllAreas as a profile name.
Alternately, use the following steps. Note: This procedure involves editing a game file; create a backup copy of the file before proceeding. Use a text editor to edit the "preferences.txt" file in the game directory. Add the line:
UserProfile = AccessAllAreas
Map and player modifier:

Note: This procedure involves editing a game file; create a backup copy of the file before proceeding. Use a text editor to edit the preferences file in the game folder. Add the line:
ModSystemEnabled = 1
Press (Esc) during game play to access the "MODS" option on the menu. Alternately, successfully complete the game to unlock this option.
Unlock MODS and Map Editor:

Complete the game.
Christmas theme:

Change the system date to December 25th and start the game. Snow will appear, and some Darwinians will have Santa hats.