Advice needed on this chicks rear!

Hi, I hatched some shipped BCM, polish and the 1 blue copper marans and this was the only chick that hatched from the Blue copper marans eggs.
She/he was the last to hatch, is the smallest, and has had the most problems with pasty butt. I have cleaned and cleaned it, used Vaseline, bacterin ointment, and all the recommended items the first few days of this chicks life.
We are on week 2, and she/he has grown in size and strength, and is doing a whole lot better now.
However I am not sure what is going on with this chicks butt. I just noticed it had more crusty white and yellow stuff directly below its vent. I took a few pics before I cleaned it and a couple after. (It seems like it has a distended belly, and the pics should help a little visually with what I am talking about) I could use any input on what is going on. I hate not knowing.
I am unsure if I should just leave it alone from now on, as long as the vent hole is clear, or if it is better to clean it off.

Here she is before I rinsed it off today.






Here she is after I rinsed it off

I had the same problem with one of mine. I finally put her butt in a contrainer of warm water and gently rub butt. Could have a plugged up butt. If you haven't done that yet it helped mine, just make sure they are dry first before you put her back. Also check heat and if they are huddling away from heat sourse, Could be causing the problem. Hope it gets better.

I read in a couple of different posts that if there brooder is to warm that is the cause for pasty butt. Don't know why it doesn't affect them all. I have done less heat and have not had that problem. Just hatched 19 no pasty butt

Thank you, I actually use the mamma heating pad method, and find that they seem to do much better with this system with regards to monitoring heat. I find that the ones that don't need as much warmth lay on top of the frame and the others that need more warmth actually go inside the structure.
I did notice that after spending twice as long today getting all of the area comepltely clean, she finally puffed up back there. First few times I was just wiping her immediate vent area, bc I though she may have some sort of scab where she possible had a issue with a unheralded navel.

Ok, so I turned the mama heating pad down, and I thought all was well.
So yesterday, I noticed the same chick started to have poop stuck to its rear again!!
I think this chicks bottom sticks out farther than its vent hole above it!!
Hmm, what to do??

I feed fermented feed from the start and never deal with pasty butt.