I have attempted a number of solutions this morning. My conclusion is that is that changes in either migration or on_config_changed don't seem to propagate to the tech tree. There may be something the game engine is doing between them and game start. Even on_player_joined doesn't fire in either instance.
I could add a call in on_tick, but without being able to unregister the handler, I believe that would be a waste of performance.
The only fix, for now, is simply to research something, on_research_finished will take it from there.
Thank you for trying the mod though
