Riley the water cat

I mentioned in a previous post that Riley has what we think is an abnormal fascination with water. He seeks it out any chance he gets. Buster used to like to drink from a cup so when Riley was just a baby kitten I offered that to him as well. He immediately took to it. It was uncanny the way he got so excited when he saw the cup.
So, that has been our daily ritual. Every morning [and now several times a day] he asks for his cup and we fill it for him.

The problem is he is now obsessed with his cup. When it was empty, he would start batting it around asking for it to be filled. The original cup was ceramic, so we switched to a plastic unbreakable cup. Then he started playing with the water in it with his paw. He would scoot it across the countertop if it was empty and force it into the sink so that it clattered. Not a very nice thing to do at 3 AM!
So we started hiding it in the cupboard below the sink.
He found it there.
So we put a baby lock on the cupboard.
Last week, he figured out how to open that and squeezed himself into the cupboard. He then scooted the tumbler out of the cupboard and sent it careening down the hallway. Makes a wonderful loud noice on satillo tile!
So, now we have an even stronger ARD [anti-Riley device] on the cupboard.

It takes us two hands with two thumbs to open it. I wonder how long it will take Riley?