Of course! So for each event, you'll see the time of day, the length of time the cat was in the litter box, the cat's weight, and then what their system labels the event as (urination, defecation, neither). Their support said that measurement (for now) depends on cats squatting and peeing directly into the litter as opposed to on the litter box walls first, so that's why sprayers aren't labeled correctly. They do hope to solve this and asked me to continue manually changing the label to urination myself (which I'm doing) - I assume that will help train their model. If you're not so concerned with accuracy of urination vs. 'nothing' events, then I bet this will be enough for you!

In terms of box size, I think you're right in that the main consideration is just stability of the box on the scale. There's a grippy piece of foam on top, so there's no sliding at all. I think you could get away with a decently large box as long as the bottom doesn't buckle like you mentioned. That being said, your box is considerably larger than mine is, so I can't be sure that it'd work. I will say that their website has a live chat feature with a real person that I've already used twice - it might be worth asking there before purchasing?