Jonathan:
 
Perhaps someone here will prove me wrong, but I doubt that you
can litter train a ferret that has free run of a large room.
Having a litter box in every nook and cranny doesn't qualify
as being litter trained in my book. :-)  That's just covering
every possible spot and the ferret isn't really making a choice.
 
I have had little success litter training two of my ferrets
that had free run.
 
Duncan, our caged ferret (he gets plenty of out time) spends all his
sleeping hours in a large condo cage.  He sleeps in the top, one side
of the bottom has a small litter box and the other side has his food
dish and water bottle.  When he wakes, he doesn't have too many
choices as to where to go.  I don't think he'd want to go in his
sleeping area or his food area so there's not much left besides
the litter box and he never misses.  BTW, the cage is not left open
for him to come and go as he pleases.  It's only left open when
we give him his out time.
 
The great thing is, he is so accustomed to using that box that if he
falls asleep upstairs in our spare room during his out time, when he wakes
he'll come all the way downstairs and go in his open cage to use the box.
 
He has never had an accident and up until we got him, I didn't think
that was possible with a ferret.  If someone told me their ferret ALWAYS
used the litter box, I would have thought, "Yeah, right" but now
I know better.
 
I think that if you restrict her in the beginning and force her into
using the litter box, perhaps you could then allow her free run
(occasionally) without the problems of missing the box. If you leave
the cage open all the time, basically allowing her to do what she wants,
she may never learn where she is supposed to go.
 
  mike
 
[Posted in FML issue 0798]