Newly Adopted and Not Getting the Idea

I just got a cat from the Humane Society in my area. She is about 8 weeks old and we have been trying to litter train her and not being very succesful. She is the only cat in the house and she has her own bathroom with her food and water at one end and litter box at the other. I have been reading all of the articles I can find on the subject and have a few more detailed questions.
I have tried rewarding her for her using the litter box and now she thinks she gets a treat just for being in the bathroom. In her bathroom I have her food and water at one end of the bathroom and her litter box at the other. They are about 2 feet from each other. Is this too close for her to be comfortable? I have been locking her in her bathroom every night until we can get her trained. When we lock her in the bathroom she will poop in the litter box. I have never found evidence of her peeing in the box or on the bathroom floor. When we let her out she goes somewhere soft and pees on it. I thought that she may have gotten into some bad habits at the humane society because they use shredded paper in their litter boxes. Might it help if I used some shredded paper in the litter until she gets accustomed? Should I put something soft in the litter box so she uses that and slowly work it out? She makes no effort to go too the litter box ever but will poop if we put her in it. If she is peeing when we put her in it she stops it and holds it. What do i do?
This is my first cat and I hate having to lock her up at nights but I live in an apartment and can not afford to have her peeing all over the house. I need to teach her to use the litter box or I can not keep her and both of us have fallen in love with her. Please help.

I'd try the shredded paper on top of the litter. That might work. Until she uses the pan properly, she will have to stay confined if you cannot watch her.

You might want to try Cat Attract Litter. It is more expensive but I have heard it works wonders. If you can get her to go in the litter box several times in a row she will most likely continue to use it.

Maybe my reading skills are lacking, but I didn't see mention of a second litterbox? Some kitties are very particular about not doing all their business in the same box.

Try putting out a second box with newspaper or cat attract litter (or both?). Also, eight weeks is a pretty young kitten. Mama would still be training her, she may just need time to get the hang of it.

I agree. Also, a second box in another location where she plays. She is like a human toddler at this age. They cannot always hold it or get confused about what goes where. A second box will help until she is a bit older and has a handle on it all.

Thanks for rescuing this little one! We would love to see photos when you can Welcome!