Yeah. That's a common theme for all these renpy games. I'm frankly surprised that no one has come up with a true update mechanism for this instead of discrete re-releases. And if someone has, they need to share that code around.
Maybe when I get some free time, I'll play around with that. I'm pretty familiar with Python, but unfortunately not with Ren'py.
But I refuse to believe it's not possible. If we could download just a couple of hundred MB instead of in excess of a GB for each version of each game like this, I think a lot of people would be happier about it.
Edit: Just proofreading.