A note: the thing about the black-and-green robed mages talking while inside the government building happened to me a long time ago - before I ever knew there were such things as mods. So it might not have anything to do with Edwin. I has only happened once for me, despite having played through that scene lots of times.
I'm not even out of the dungeon yet in my Edwin-game, so no bugs yet.
This mod sounds very promising, just one question though, if you don't mind: is it possible to play the mod if you start a new game in ToB? You said the note depends on how you acted in SoA, but what if you either started a new game in ToB or never did the Windspear Hills quest in SoA? It's just that I lost all data on my harddisk some time ago, and among that my savegames...