I can confirm it is 3 3 digit numbers. The color one will probably be the hardest, but is obvious if you find it. Constellations is pretty straightforward.
I have still found too many numbers to be of any use. Mostly since I don’t know if there is any signifigance to certain numbers being written out as numbers instead of letters in earlier chapters. I have a couple of guesses for the color but at least one of the guesses has two colors that barely have a difference in shade to me. I’m guessing the constellation may be being hinted at on the button itself but a look over 88 constellations doesn’t have anything that immediately pops out to me.
1. The numbers are in chronological order and that's all I'll say.
2. If you're guessing the colors, they're incorrect. It'll be obvious when you find them. Like I said through, this one is probably the hardest to find.. It possibly could never be found.. but there is a hidden hint to help you find it in game, which I'm sure many people have stumbled upon but don't quite understand the meaning.
3. Constellations have nothing to do with the button.
My best guess as to what the colors are supposed to be is the Sticks & Stones sign in New Hage. Although even then the Sticks & Stones text is green white red while the sticks and stones symbols are red green red. Regarding the constellations, if the button itself isn’t showing a constellation then the only two times anything overtly or even somewhat related to the night sky would be during the Forbidden Fruit scene and the Wall Vines game over.