On our last trip we started to use our camp oven more. Works well and more on some of our meals later.
For now I just want to mention that it is important to 'cure' a cast iron camp oven to stop it rusting.
To cure anything cast iron, we first clean and dry it. Then coat the inside surface with cooking oil (you won't have to worry about the outside as it will be coated in soot from the fire) and warm the item over a slow heat for a fair while. The theory is that the heated iron will allow oil to impregnate the material. You may have to repeat this process a few times but eventually you'll get a rustproof item that is easy to clean.
A good website for camp oven info is http://www.aussiecampovencook.com/