Late feathering chicks usually are boys from what I am experiencing here. The girls tend to get their all over feathers pretty quickly and the boys look naked down their back for quite a while. That is not always the case, but tends to be with my birds.
As far as the pasty butt, keep it clean and it will clear up with time. The birds with the nasty butt their whole life tend to be the fuzzy butted ones. They have so much fluff that their poop or mud on a rainy day, gets caught in it. Pasty butt can be caused by stress, short backs, and a whole host of other things, but it always clears up. Now a watery behind, not sure of, try some apple cider vinegar in the water and see if that takes care of it. You could also feed scrambled eggs, some oats, cooked quinoa, sweet potatoes. That works for me. Their bellies like it and it seems easy to digest and move on through.
How are the babies doing otherwise. Do you still have 5 or are you down to 4. Araucanas can be so frustrating most times. Then I go outside and look at my babies running around and think yep this is what I love.
Lanae