Brand New Owner

[El Lobo]

I just got my new 2922KS last Friday! We towed it from the dealer in Portland OR to Stevensville, MT, going over several mountain passes. It was a new experience for us since we have never towed anything this large. Plus it is our very first trailer. (We had always tent camp before.) I am still learning how to back it up and make turns correctly. We got very good gas MPG even going over the passes and having the AC going full blast (it was hot).
I just sent in my application to join the forum. I have already learned a lot by just reading what people have posted. Right now I am 'camping' at home testing out all the features to make sure they work and to see what items we need on our camping trips. We already have a few trips planned for next month. I do have a question. At the dealer, the guy that was showing us how to operate the stove, AC, etc, (which we only retained about 10% of what he said since it was done so quickly), said that we should keep the propane tanks open while towing so the refrigerator would run off them instead of the battery. Everything that I have previously read have stated that, for safety reasons, they should be turned off. Who is correct? Plus, on these hot summer days, is it okay to run the refrigerator while towing and drive 200-400 miles between camp sites? Any help is greatly appreciated!