For stink, I'd recommend what I have to do with diapers. Heat and more water. I have to add 2-3 gallons of water to my diaper loads because otherwise there's no water to actually agitate. Sit and watch your FL sometime as it starts it's cycle. When it's finished filling, open the door and check how much water is left. For something as absorbent as towels (or diapers), I'd be willing to bet there's not a whole lot. I just fill a bucket with hot tap water, open the door and dump it in. So long as it's below the level of the door, it's not a problem. If you need to add more than that, you can pour it into the detergent cup, but I always wind up wearing it that way.
With my dipes, I do a first (cold) wash, which gets the surface stuff out, and then a second HOT wash, both with extra water. And just by switching to this method, I've managed to remove the stink problem I was having.