Minor update, forgot to change builder spawn unit back to builder after using this script for testing.
If you want to fix yourself w/o another download, just change "UNIT_MISSIONARY" to "UNIT_BUILDER" in the top section of the lua.
For hot-seat:
Remove the line:
Events.LocalPlayerChanged.Add( OnPlayerTurnActivated );
near the bottom of ScoutSpawn.lua
It will cause the script to run twice for players other than player one.

Extra Human-Player Units at Game Start 1.05
Spawns extra Settler, Scout, and/or Builder units at start of game.