So this is what I've ascertained...
When I was building Patton scenarios, if you gave P1 a French-style TC he could automatically produce P1-owned French-style civilians. Apparently this was identified as a bug and eliminated.
However, the same effect can be easily achieved, with considerably fewer triggers than oXo's method.
Let's say you've spent a lot of time creating a beautiful town in the style of Korean architecture. Now you have French units invade and take ownership of the town. Wham-o, suddenly the whole town becomes French! Instead of getting the feeling of foreigners occupying a town built by another culture, you have a very unrealistic magical transformation going on.
So instead of a "change ownership" effect, try this:
- Remove the Korean buildings
- After a .01 pause, create new Korean buildings in the exact same spaces, but owned by the French civ
- Modify P1's tech tree to allow him to produce Korean commoners, Korean soldiers, monks, or whatever else is appropriate to the captured buildings.
- The buildings will now create Korean units owned by the French Player -- "locals" who are now working for the occupier/liberator.
- The Korean commoners will be able to build only Korean-style buildings. Whatever type of Korean buildings P1 now controls will automatically be available for the commoners to build, and only that type --- unless you modify P1's tech tree to allow him to build other types of Korean structures.
- French peasants will still come out of French TCs, and they will only build French style buildings
- The newly-built French-owned Korean buildings will have all the bonuses normally assigned to French buildings
The main thing is that an elaborate set of replace object-with-object triggers isn't necessary to get the "authentic local units" popping out of their respective buildings. Just enable P1's tech tree and it will happen automatically.