My version is 3.03.1047, I play this game since 15/16th July 2016 and encountered the Brighthollow bug as well.
I followed the workaround to disable party auto level up in the option menu, but regardless which save game I chose, the upstairs map did not load.
Screen turns black and I get the message it can't be loaded to prevent save game corruption.
What shall I do now? It's ok for me, as my chests are empty there, but I am a bit scared I might corrupt the game if I carry on.
Btw, as soon as I started to play POE, it felt like coming home after many years in the RPG desert
I love it.