As with Barbetween, this cannot be played with a guest account; you have to register. Sorry. (I have more or less worked out to properly reset the guest accounts, so that people can try these things without stumbling into a half-solved world from a previous guest. It’s not a priority this month, however.)
I opened and solved the three ages in the three corners, so the three crystal plates are glow. I set all sliders in all sidepaths to the numbers that are on the glow plates. This give me rune. I touch the rune, then again in Soran Veldt. Effect is, there’s some more water in the basin. I do not think able to do anything more with the basin. Is Soran Veldt something I need to solve before I am complete with Salvanas?