Keys on Doors...

[GoranGaming]

void OnStart()
{
AddUseItemCallback("", "studykey_1", "mansion_2", "OPEN", true);
}

void OPEN(string &in asItem, string &in asEntity)
{
SetSwingDoorLocked("mansion_2", false, true);
PlaySoundAtEntity("", "unlock_door", "mansion_2", 0, false);
RemoveItem(studykey_1);
}


You forgot to declare mansion_2 two times in the OPEN function.