Thanks everyone, for the warnings about cats. When I designed the cage that was definitely one of my considerations...to make it as cat proof as possible, and have most feeders outside the cage. As long as the birds can't get out, I'm positive the cat can't get in!
The doors all open upwards, so their weight makes them drop down automatically when I pull my hand out. Same with the door at the front where I remove the tray. I can quickly remove the tray and drop the door down and lock it, while I wipe the tray out and replace the paper.
I only open the cage once a day to give them eggfood or millet sprays. (Well twice, on the days I offer bath water.) And that feeder is at the end farthest from the nest. All other feeders (water, seed, kelp, oystershell/cuttlefish/charcoal) are accessable from the outside.
I figured that I would try to stick to my usual routine and just hope for the best. I considered not vacuuming until the eggs hatch, but I don't think I'd better leave it that long! Or my sister's face will look like this:

Will try to keep the movement to a minimum though. They do pop out of the nest a lot quicker than the societies would have. But so far they go right back in pretty quickly.
My cat can't knock the cage over. Not even if she hung from it with her claws (if she had them). It has legs that sort of embrace the top shelf of the stand, to keep it from sliding off, that makes it impossible to tip it over. I tried.

Certainly would take a lot more than the weight of a dog or cat, or even a person bumping it, to ever be able to dislodge it or tip it over. My big fear is that they will somehow slip out while I put the treat cup in, or the bath water. So I am very, very careful.
When my little shih tzu was a puppy, one of my young societies slipped out of the cage while I was cleaning, and Tody grabbed it. She was so fast she even beat the cat to it! But I hollered at her to "drop it"! And to my surprise, she dropped it right into my hand. It was a miracle it wasn't hurt.

So I'm as careful as I can be ever since then.
I'll just have to sit back and wait now, to see what happens, since I can't peek anymore.

Will let you know if I hear any little peeping sounds coming from the nest. Does anyone know what I could sell the babies for, if they do manage to raise some to fledglings? I paid $70 each for mom and dad. I'm located near Vancouver, BC, Canada. I was thinking about maybe $30 each? Would that be a fair price to ask? Or too much? When I had societies they sold in the pet stores for $10-$15 and I sold my babies to the pet store for $5 each (quite a few years ago now). I'd rather sell any babies I might get, to individuals, or breeders so will likely post an ad on Craig's list. Just wondering what you all think is a fair price.