TTG
The save game editor only allows you to
change nations
+/- money
+/- time
I know it is possible, according to the Cheat section that you can give yourself all tech and conversly strip all other nations of their tech, (Just look at the example and thing about it...)
Playing around with said example I have allowed myself to pick up a smattering of techs from all levels but there doesn't appear to be anyway to figure out what combination give you what, like instantly getting all tech upto Gunpowder instantly.
James