The golden skulltula situation is pretty confusing. Let's say you get all the child skulltulas, and then turn into an adult and get all the adult skulltulas. If you turn back into a child, the curse has been lifted... even though there's still seven years until all of the skulltulas are destroyed. Even more confusingly, they know it was you who lifted the curse. So, were the people cursed for those seven years or not? There's also some skulltulas that exist as an adult and a child, and if you destroy them as an adult then they're destroyed as a child.
Similarly, if you make a change to an adult dungeon (e.g. open a chest, unlock a door), and turn into a child and go into that dungeon, the dungeon doesn't revert to its original state. This is probably best seen in the MQ Spirit Temple, where you can drop and open the chests in the first room, and when you come back the chests are still there, opened. Very confusing.