Difficulty filling water tank
Chris, You probably already know this but will throw it out there.
In the photo, the little screen is the vent for my freshwater tank. If you have the same type of set-up I wonder if your vent line may be plugged or kinked.
I had a similar problem with the fuel tank on my truck. It was taking me 20 minutes to fill my tank. I had a 'ell of a time figuring it out too! As it turned out the vent is routed through a filter canister above the spare tire and its vent had gotten plugged with mud.