It is still the case that the McCanns have described their shock (perfectly reasonable shock, in my opinion) that the window that could not be seen by them or their friends was found "forced" open when they believed it had been locked.
But the McCanns *would* describe that shock even if they were "acting the part", yes? This is the point, when the people upon whom you are relying for information are those who have most to gain from making sure the information given puts them in a reasonable light, you cannot simply take their word for it. This is why us doubters keep asking for corroboration from independent witnesses.
e.g. "Gerry and Dave went out searching on the beach" - who says so...? "Kate McCann". That doesn't count as evidence as it's in her interests for that information to be believed.
Take it to an extreme - remember the Shawshank redemption scene? When Red says he's the only guilty man in shawshank as all the others are innocent? You can't trust the (uncorroborated) words of those who are still not cleared (officially) by either the Portuguese or Leicestershire police forces.