This is basically what happens, at least on my Mac - it complains about it not being a valid SYLK file, then I think, "I have no idea what that means", then I d

This is basically what happens, at least on my Mac - it complains about it not being a valid SYLK file, then I think, "I have no idea what that means", then I dismiss the error and it opens it up as a CSV. At least now I know why!