When litter training, make sure there are no soft blankets or absorbent material on the floor in the cage.
If she pees on the floor, wipe it up with some paper towel or tissue, and place that in the litter box. Then, clean the area with 50/50 vinegar/water.
The cage will need to be kept very clean. Wiped down with vinegar/water a couple times a day to keep the non-potty area smelling clean for the bunny and the potty area smelling like a potty.
Keep it up, and she should get the idea. Sometimes it takes a couple weeks of constant clean up, but she will catch on eventually. She may never keep all her poops in the litter box (especially when not spayed) but she should get most of them and all the pee in the litter box.
I just use a hand broom to sweep up stray poops, very quick and easy.
-Dawn