Karl Lentz got his children back after they were taken by agents, too. He tells his story in detail on his Talkshoe calls. Type "Unkommon Law" into the search on Talkshoe. He got "immediate restoration of his property" using common law language. This is not the common law with statutory stuff in it, this is another kind purely based on, "was there harm, injury or loss?" and using very specific non-statutory language on paper in four sentences or less.
His clips are also on YouTube, just do a search for "Karl Lentz property."