I have a young ferret, Loki, that is resistant to box training. I built her a multi level wooden 'bookcase' style cage. For the first 2 weeks I contained her to the lower 2 levels. She began to use the box nearly everytime. Today I gave her access to the upper levels and the training went right out the window. She will not travel down to eliminate and there is not room for a box on the upper most level. Any ideas? I do plan on lining the floors with a rubber mat to prevent odor from staying with the wood. I have found Home Depot sells the liner that goes beneath a shower. [Posted in FML issue 2944]