Thank you! That appears to have worked, and I find that very interesting since I don't understand the syntax you've used at all. I see the setting for Filling that seems to match:

{i1 -> {p1,g1},...}

...which is described as "use directive g(k) for the kth filling", but I really don't grasp how something as simple as {1->{2}} manages to extract the appropriate values from the two TimeSeries. The FullForm of a TimeSeries seems far more complicated than such simple syntax would seem able to parse.

Are there other examples of this available for reference? I'd really like to understand better HOW this works rather than just seeing that it does. :-)

And, thank you again for the prompt and accurate reply!