So, turns out that the tank valve is bad. Disconnected everything from the tank valve and opened it. Opens slightly and then closes - the safety mechanism is faulty. Talked with tech support at Lazydays and found someone who was really knowledgeable - he had a similar problem. Got to empty the tank and replace the valve. Gonna see if a LPG distributor can assist me with that, or I will have to take the RV to a RV shop and let them do it, if I can find one that will work on a propane tank!!
jwmll, probably that excess flow preventer you were talking about.
Thanks for all of the help!! Happy Thanksgiving!!!!