Don't know if I mentioned 'Battery Mat' to you. You should look into these because they really help reduce the amount of corrosion that accumulates by absorbing the fumes. I put a couple of the mats under the battery slide out tray and cut up a few mats to put along the sides of the battery slide out tray. I tried to cover as much of the floor under the slide tray as possible with the matting.
Battery Mat home page
I also put 1.5oz of mineral oil in each cell of the battery. This also helped quite a lot and helps keep the water in the battery. You need to make sure that the water in the battery does not fall below the top of the plates in the battery though.
Don't know why the tops of the batteries are wet. Could be one of 2 things: 1 - a leak in the battery compartment, 2-batteries overfilled. As for the red stuff, that is a corrosion preventative paint that FR puts on the terminals and a couple of other things in the battery compartment to prevent corrosion build up. You probably can buy it in an auto parts store to re-cover the areas where it came off.
Hope this helps.