I have heard that Forest River got some of the quality control issues resolved but it doesn't sound like it to me.
The Fresh water tank is not easy to get to. If you crawl under the street side just in front of the rear wheels you can find a white soft plastic tube hanging down. That is your overflow line. I understand that to pull the fresh water tank out you have to pull the generator out first.
I've had a similar problem to your issue with the water tank not being full. Here was my solution.
1) As you are filling the tank, turn on the water pump and make sure to fill the water heater and all the lines, toilet, sinks, shower. I found this simple trick saved me 15 gallons of water. Just didn't occur to me to do this as I was filling the tank.
2) I extended the overfill line with 1/2 PVC pipe so the water comes out right in front of the rear tires at the outside edge of the coach. Easy to get to. When the tank is full I put my finger over the end of the line to stop any syphoning that is going on. It takes a couple of times but then the water stops.
Those two things stopped my water loss and after filling the tank (but before my wife gets into the shower for a 30 minute hot water soak), I check the gauge and it does read full. All bets are off once she takes a shower. :-)
While we are on water issues I have an objection to the size of the grey water tank FR put in my coach. It is only 40 gallons and if fills up very fast. The holding tank is also 40 gallons and that works just fine but the grey tank should have been 60 gallons.
Can't help you with the tile and my coach didn't come with an inverter, I had to add it later. I don't have a problem with it but don't use it all that much. I also added a solar panel up top to recharge the batteries.
Gary, Cindy, Reacher (Maine Coon), and Vivian (in spirit only now).
Retired: July 31st, 2013 and loving it.
2011 Coachmen Encounter 37 TZ pulling a 2012 Wrangler Unlimited Sahara. Many upgrades, additions, mods, and changes.