Yes and no.
She could change textures on the fly, but model stuff was tied to the model completely. She could change out aspects of the model before starting, but not while in game.
I believe the goal is that she could, say, decide she wants to change clothes mid stream, and be able to do it, without loading screens. No idea if she can do that now.>>5269822
Spaghetti code is called that because things that shouldn't be related are all tangled up because of dependencies. I'm guessing some physics stuff was tied to the room, and when her breast size was changed, that parameter was changed in the wrong spot, then from then on the program would crash without the right parameter from the larger breast size.
This is why the new code system was a big deal to the three people that cared about such things. Nice clean code, letting you do what you want. It'll probably only take a month before it's a jumbled mess again, though.