u can use user.empire_script the in documents and settings/YOUR USER NAME/Application Data/The Creative Assembly/Empire/scripts
to get here u need to press the tool tab, the choose folder alternativs, showing( dont know if its right but in swedish its visning
) the u check the box show hidden files and folders.
note: u need to create a note pad dockument named user.empire_script and in it paste the following line: mod "natvie_americans.pack";
when u save it u save it as a unicode dockument, u change that on the codeing tab, ist under the fileformat tab.
this should work, if it dont, u pm me and i'll managed something out