What kind of litterbox do you have for them Brandy? I found that you pretty much need a litterbox in every corner of the cage otherwise they will go there anyway.
I just have one in one corner. They sleep in one of the corners (even though they have the Dice hammock/bedding thing) and so from what I read they won't go where they sleep. I have there food and water in another corner (although I'm thinking of moving those higher now that they both climb to different sections of the habitat) and then their pooing in one of the corners. I'm thinking of moving the litter box there since they are already going there. They like to move the litter box to the middle of the cage, so I'm thinking of getting a hole in it and then securing it to one of the corners.
Also this morning they did not go on the shelves during the night, so happy with that! The people at petco, and from what I've read online are saying that if you scoop the poo into their litter box they will eventually understand that is where they are supposed to go. Hopefully that happens. I think after this bedding is changed, I'm going to use old (but clean) shirts as the bedding and from what I've read online they are less apt to use that as a place to go.
Sabriel is upset with me, she doesn't like me spending any time with them, but then when I try to play with her, with her toys she's always too interested in them to play. She also keeps sniffing her cage from when the ferrets were in their yesterday. I hope eventually she gets used them, I didn't realize that this would be so hard on her, I didn't expect her to be frightened of them - yet curious of them at the same time. They've sniffed noses a couple of times now, maybe eventually they'll play together but it'll be a long while before I even chance it.