If you look at the states in yugoslavia you'll notice that they slightly changed the state borders for montenegro and macedonia to fit more with what they actually were considered to be contrary to the post invasion states where bulgaria also occupied the strip where pirot and vranya lie for example. Or to take an italian example the montenegro state used to basically circle around albania to represent those provinces that were annexed by the italian protectorate of albania. Thing thing being that as far as i know those parts never belonged to montenegro and so the only situation where that state border made sense was if italy occupied that part.
They also changed the polish states around a bit which has made the molotov ribbentrop pact borders a bit off i think. That again being an arbitrary line drawn by two occupying powers so I'm not even sure if state borders should be designed to fit around those specifically.
I wasn't trying to say it wasn't changed, just that it wasn't noticeable to me. Which makes sense, I rarely mess with yugo and when I do its a quick conquest, set garrison, then forget about it. I rarely use Molotov Ribbentrop either so I guess I'd never see those new lines as well.