Ferret poop and aggression

Question
Hello

I have 3 fuzzies and I have three questions for you.

1) When I let my ferrets run around my room, sometimes they refuse to use the litter boxes and instead poo outside next to the littler box (that's why I'm also using wee pads in the corners of my room). The litter boxes are always clean and smell fine. Why are they doing that?

2)No matter how clean I keep their cage and litter box, someone is always stepping in poop and tracking it around the cage! Why on earth would they step in their poop?!? Is there anything I can do to stop this?

3)One of my ferrets,Kumo,does have adrenal disease and I'm going to have melatonin implants administered by my vet. I've noticed he's very sexually aggressive with my female ferret Natsumi. Sometimes I'll hear her screeching and hissing and I'll go into my room to find him biting her neck and trying to mount her. I separate him for a few hours when things like this happen. He goes into a separate cage. It's like he'll be good for a few days and then go back to being quite sexually aggressive. Am I doing the right thing by separating him from the other ferrets?

Answer
1) Ferrets sometimes don't use a litter box.  They are not cats and therefore not as good at using the litter box.  I can't give you a scientific reason ferrets have odd litter habits, but I believe too much space, too small a box, not enough boxes, and early experiences all contribute to these issues.
2) similar to above - try a larger litter box.
3) The aggression will only stop when he is treated for the adrenal....sorry!