Oh, I hadn't thought that litter might be a problem. In fact we did just change litter recently, not long after she had started pooping on the floor. I thought we'd try out this wheat litter they have.

She's been shut in our room for two days, and finally this morning she pooped! Even better, she pooped IN THE LITTER BOX! The cover was off the box at the time but I'm hoping she'll accept cover on, eventually. It was the new box, my thinking at the time was that she'd prefer a box that hadn't been used by the kitten, but I guess she might have preferred the old box because she's used to it. Doesn't matter now though.

Once she decided to poop in the litter box, she has no desire to leave Kitty Prison. She would call it--Kitty Haven. I decided I'll let her out if she wishes, but we will keep the kitten out of that room always, so she has a place to escape.

Thanks for the help!