of course, its very easy to do. You just edit the sandbox file you want to have affected by this code change. Example code: 1) The Reward Parameter 1 shown as is the line of of the unit you are to be rewarded with at at certain tech level. The Tech Level is dependant on where you add this type of code into. Just for information this is in my Tech/spawn era Level two. 2) Reward_Param2 - is the unit to be removed from the game at that tech level era. Event name can be what you like I called mine unlock_stormtrooper. ok, thats eample code and it should be used in any spawn time era you want to be affected by the changes, through out the sandbox files you want to edit. Only add 1 instance of the type your changing. Although the actual reward parameter doesnt matter if your just removing a type of unit - it will still work. General usage: Removes old unit and rewards player with new unit at a given tech level. Hope this helps.