I disconnect my battery in storage and take it home to charge it when it's going to be a while between camping trips. Just pull the black wire. I don't put mine on a trickle charger and leave it (unless you have a smart charger, which I don't). On my motorcycle I will use the trickle charger for a couple of days at most. Over months it will dry out a battery.
The gauges seem to be working on my TT. On the previous motorhome I used it so much that I forgot that the gauges were there. I never used them because I just kinda knew the status of all the tanks. On the new TT I really can't say that I ever use the gauges. When we started RVing our first TT didn't have gauges for the tanks so, I guess I'm still in that mind state. In my view they aren't reliable and often provide inaccurate information. On the black and gray tanks I can SWAG the levels pretty accurately. In the guessing game it's the fresh tank that's harder to know. But, we don't dry camp very much at all so, we almost always have city water connected. Therefore, I don't care how much is in the fresh tank.