You were on the stream so i realize that you resolve the problem, for another guys having the same problem, activate the beta mode of steam on the parameters tab.
It will be really good if you can manage the archives what replaces the patcher, anyway i did a backup of my data folder for futures versions o/.
By the way, i forgot that in some points of the early games, i had to play the mod in a vanilla version of the Steam game, without any mod except the yours, for example, in the motorbike minigame, and when i "get" Aeris from a Phoenix Dawn, in this one, i had to able Aeris on my Phs and party via Black Chocobo, i think it's a model problem, there istn any pop up from the error, just the screen turn black or freeze, then i have to stop the application, there is a windows with a "An unknow error has occurred" message, but as i said, i think it's about models problems.