Help using "ecmlsrmle" or "ecmmvnrmle"

I have no idea what the "Design" input parameter in either of these functions is (ecmlsrmle or ecmmvnrmle). Is this a design matrix? Is this some kind of information cell input to help select an algorithm e.g. 'polyfit'? I'm completely lost here. Any help on that format would be greatly appreciated.

Has anyone ever used either of these functions before? If so, what did you use it for, perhaps you can help me.

Thank you, Tom