These techniques seems to work

[Cadburry]

After Cadburry does a poo on green we remove green tray and leave only white rim. He then does a few pees on white.
When its nearing poo time we replace the green tray.
We mix it up a bit as well, sometimes we dont remove the green. sometimes when we put green back we dont put any litter on it, sometimes we put lots of litter and sometimes just a little.
Bedroom door is always closed (except when we're asleep off course)
Lots of toys on the floor of the batchroom.
Treats after poo/pee placed on floor below toilet.
Play with him in bathroom to make it a safe place to be, a place that he readily goes to and isnt scared there.
When its poo time (he announces) we do the potty dance on white.
so now.... he has gone 10 days on white. I think the transtion from green to white is working using the above mentioned techniwues.
It's taken 18mths, we got him to green pretty quickly but always had difficulty going from green to white.
fingers crossed

[Norwegiangirl85]

Wow, 18 months - you have really been patient

I'm crossing my fingers for you!!!

Did you try the cardboard method from green to white? That worked for us

Keep us posted!

[Cadburry]

Every time we go on a holiday for 2-3 weeks Cadburry goes back to the breeder to be looked after. There, he has a litter tray on the floor. So when he comes home again we've gone backwards in our training.
So it's taken 18mths, but now he's been on white for a couple of weeks without any problems. yay!
Maybe the toilet paper helped, see here....

http://youtu.be/q84U-msiwrY