Welcome! Settler Massacre is an old and famous RMS that used to be very popular on ESO. However, it was not yet uploaded anywhere, so the only way people could obtain the map was by joining a room on ESO that was hosting it, or getting someone to send it to you.
Settler Massacre is a very simple map, you spawn with only a town centre and need to rely on shipments for your initial resources and units (the map is completely blank with no resources anywhere).
While I (Anterior2) uploaded it, the map itself was ostensibly created by Rodonna of the Rutilus Vox clan (http://rutilusvox.webs.com/ - website is old, last updated in 2008).
However, thanks to a post by the user Aizamk (http://www.ageofempires.com/Forums/yaf_postst653_Settler-massacre.aspx) I discovered that the map (the .xs file) is an almost exact copy of the example code in M0nTy_PyTh0n's RMS tutorial (http://web.archive.org/web/20100421112530/http://hyenastudios.mugamo.com/aoe3rmstutorial.htm). Rodonna even left the part where you are supposed to insert the name of the author and title unchanged ("/* A SIMPLE RANDOM MAP - by Author - Version 1.0 */"). Rodonna does appear to have created the .xml file however.
Inside the .zip file alongside this readme should be 2 files. One of them should be called SettlerAmbush2.xml and the other called SettlerAmbush2.xs. Please do not rename them.
Step 1: Select these two files and copy them (right-click and select "copy" or press ctrl-c) (depending on your version of Windows you might need to extract the .zip file first).
Step 2: Paste the files into the relevant folder. This will be different for different users. The relevant folders are listed below:
Vanilla players (people with no expansion packs):
C:\Users\USERNAME\Documents\My Games\Age of Empires 3\RM
--(replace "USERNAME" with the name of your user directory - typically your Windows login name - this goes for the following 2 folder paths as well)
--(Windows XP users will have a different folder path, just find your "My Documents" folder and then "My Games" and "Age of Empires 3" and finally "RM" - This goes for the following 2 folder paths as well)
The War Chiefs players:
C:\Users\USERNAME\Documents\My Games\Age of Empires 3\RM2
The Asian Dynasties players (and people who use both The War Chiefs and The Asian Dynasties):
C:\Users\USERNAME\Documents\My Games\Age of Empires 3\RM3
If for any reason the game doesn't detect the maps in that location, or if you want all users on the computer to be able to play the maps, then copy the files into this folder instead:
C:\Program Files (x86)\Microsoft Games\Age of Empires III\RMx
Delete the "x" at the end if you play without expansions, replace it with "2" if you play The War Chiefs, and replace it with "3" if you play The Asian Dynasties or play both expansions.
If you don't have a 64-bit version of Windows installed, you should replace "Program Files (x86)" with "Program Files" (or where-ever the game has been installed to).
If you had the game open when you copies the files, close it and then re-open it again.
Step 1: Open the game
Step 2: If you are playing online, log into ESO and create a room. If you are playing singleplayer then set up a skirmish game.
Step 3: Above where you select the map for the game, there should be a check-box called "Custom Maps". Click it so that the green tick appears in the box.
Step 4: Select "Settler Massacre" from the drop-down map selection list.
Step 5: Set up / organise players, teams, and decks how you want them.
Step 6: Press "Play" (or press the 'ready' box on ESO).
Note: The AI gets stuck on this map because there are no resources to gather. It is best to play this map online against other people.
To contact me, see: http://aoe3.heavengames.com/cgi-bin/forums/display.cgi?action=ct&f=12,38984,,10#contact