I haven't rebuilt Chapter 1 of Serenity yet. As I said, I'll probably do a new build of all of them upon this next release for Serenity Chapter 2. And yes, it is an 'out of memory' type error. Nothing changed in the game files outside of adding images, animations, sounds, and dialogue. The animations have been done using the same format for years so it isn't that either. MS is always breaking shit, just seems this time Renpy was directly affected.