Cat Learning To Flush The Toilet
Initially, yes, my daughter's kitty was frightened by it but after realizing that it got rid of that stinky stuff in the toilet, it was easy peasy from there.
Of course, the shiny sticker that comes with the kit helps; however, training her to be comfortable with it also helps. In order to do that, I would put treats where the sensor was so she would associate yumminess with toilet flushing. Just after a few time, she was able to pick it up and has been exploring on her own, as the next video shows.
I do know that it's a great option and hope your kitty can pick it up. Of note, every time I introduce something new, I do leave her in the restroom when I'm away so that she doesn't have accidents elsewhere and motivates her to learn it, because, well, what else is she going to do in there?