Actually it does all work. I wrote some tests that verify it. I think my first question about index and cur works out because both are set to 0 -- and 0 is correct as the starting value of an array offset and index. And in the other case I believe it's intended that the two values are the current and next values, respectively.
Nevertheless let me post a patch that rearranges these Iterator/Element implementations in a way that is perhaps more consistent across the three classes in naming and structure. I think there are a few opportunities for streamlining too -- for example these static inner classes are taking a reference to the enclosing class, when making them non-static gets you that for free. (There's still a reference there, just synthetic.)