(2) That's probably right legally, but if the rules were more logical it would depend on who cancelled it and why! - there's a lot of difference between, at the extremes:
(a) the student deciding that the weather is lots worse than forecast and stopping the test without the examiner saying a word (student making correct command decision) and:
(b) the examiner having to take control and cancel the test because the student was just blundering on into weather they couldn't cope with (student not ready for test, shouldn't have been up there in the first place).