I have been full timing now for 2 years. The fridge got set to 'auto' when I moved in and it has not been changed since that day. I have been up and down mountains in Colorado, Montana, Wyoming and in just about every other western state as well without problems. Also up and down Monteagle in East Tennessee on I-24 several times.
I have a diesel and always fill up after I have set up camp so no danger there. If I was hooked up and needed fuel, as long as I was at an all diesel island at a truck stop I would not bother to turn off the propane. If I had to fuel up at a combination gas/diesel island I would turn it off.
Tim