A friend just sent a recipe for marmalade, using Yuzuquat, which he was trying. He said in turned out good. I have copied it from the email he sent. You might want to try using it.
"I took 10 nice Yuzuquats, cut them in four or five slices each, removed the seeds, then cut the slices again so the peels would be about 1/2" in long. Then I just put everything into a pot with 2.5 cups of water with 1/8 tsp. of baking soda, brought to a boil, and the simmered for 10 minutes. I then put in a package of pectin and brought to a rolling boil, added the sugar, and then boiled hard for one minute."