Thanks everyone for the responses.
In response to an earlier reply we are using a generic bubble foil type insulation. We had a local seamstress sew velcro strips onto the top and bottom of it thus allowing us to attach it to the camper. The width is only slightly wider than the fabric material (pvc coated nylon?). We must remove/install every time we pop up and down but this process takes less than 3 minutes. The catalytic heater we are using is "the wave" by Olympian run off the standard 4wc external propane tank via a quick connect/disconnect fitting installed just to lookers left of the sink and faucet. We are also using an additional "Mr. Buddy" heater now that we are in Canada.
Folks are right the 4wc might not be the best tool for the job but it is what we have for the season so it is what we will be using and expect for this ice production facility we have created 4wc is still the top choice for us and what we do. Usually we are in the intermountain west traveling, climbing, skiing between the deserts and the alpine with a lot of time spent in the eastern sierra. On almost all points except for this ice issue 4wc meets our needs so I stubbornly refuse to give up.
We are going to experiment with various approaches to this problem over the Canadian winter so if we have any revelations or breakthroughs i'll be sure to post.
Thanks!