The version numbers are simply dump revisions. Someone who originally dumped v1.0 might have done something wrong, resulting in a bug (like one missing graphic tile or something as small) that might not be seen when emulated, but rather when it's played on a copier or on a flash cart. Take note though that some translations (which is not the case here since the original rom is (U) but anyway) only work with the 1.0 version of the game. In short, you're fine with the v1.0 you downloaded earlier, unless you find something wrong with it.