have you read any of the tips on toilet training bunnies ?
If you're going to let her wander around, it may be any idea to use a litter tray in the room too.
If she wees in the same spot, use a tray there.
If she uses different spots, there is probably a corner that she uses too. Put some newspaper down in the other areas and a litter tray in the corner. If she pees on the paper, move it into the litter tray so it carries the smell with it.
Its a bit trial and error - but after a while you can normally find the right spot.
Good luck - how's she doing btw ?
Martin+Pam