I need to get a new litter tray - very exciting I know - and I prefer the ones with a roof on, which my little man uses now. However, all the ones I've seen have a door on the entrance, which I assume works like a cat flap. My Felix has never used a cat flap in his life, so how easy do you think it will be for him to adapt to using a litter tray with a flap like door? I would actually prefer these type anyway but of course if he can't figure out how to get in, it will be a waste of time anyway. While quite sprightly, at 15 he is getting on a bit, so I'm not sure he will adjust to the new set up! Does anyone have any such experience of teaching their old boys/girls such techniques? Thanks