I purchased an orange marmalade while I stayed at a B&B on the island of Aero in Denmark. I was fantastic. The ingredients are:
organic oranges 18%
sugar 27%
water 54%
lime 1%

I have two questions: how do I convert the % to weights or ounces?
And the rinds where brown (look toasted), but not burnt. Has anyone made that color? Did they use blood oranges? The flavor was more robust. Any ideas are appreciated.

The math part is fairly simple, assuming you will not be using an outside pectin source like Sure-Jell, Certo, etc.

For every liter (1000 cc), you will need:

180 cc (3/4 cup) organic orange pulp
270 cc (1-1/8 cup) sugar
540 cc (2-1/4 cup) water
10 cc (2 teaspoons) lime

Please note that my US conversion is not completely accurate, but is as accurate as I can get.

As for how you would put your orange marmalade together, I suggest you Google "Recipes Organic Orange Marmalade" (no quotes). This might give you an idea of what type of oranges to use (Seville oranges sound good) and how to put your marmalade together. I find making marmalade is more time consuming to make than jam or preserves.

As for the rest of your questions, I haven't a clue. Sorry.

Please let us know how your marmalade comes out and the process you used to make it.