Using Vixen's Profile Editor, I created 4 channels for each Aether that I had. One White, one Red, one Green, and one Blue. I assigned the channels and colors the same way as I did for the channels for my Express controllers. And of course, the Aethers' channel numbers have to be set to match Vixen.
For the Adjustable Preview, I created a grid of the White, Red, Green, and Blue pixels to simulate the floodlight on the walls of my house (Note that the pixels in my Adjustable Preview are fairly small, so I can squint and stand back a few feet and all the RGB channels blend together to get an idea as to the final color). Even though the adjustable preview pixels are sort of "transparent", I did notice that if I tried layering all the pixels on top of each other (rather than beside each other) in the Adjustable Preview, the on-screen color representations go a bit wonky when either the R, G, or B (or white) changes from 0 to 1 (or anywhere else from 1 to 255). It's hard to explain, you'd have to experiment with it to see what I mean.
When sequencing, if I wanted to choose a specific color, I used the Edit Colors feature in Windows Paint to mix the RGB channels to get the color I want. After making note of the R, G, and B values, I then set those values in each of the Aether's channels in the sequence grid. If I want a fade from one color to another from one point in time to the other, I used the [Shift] Ramp/Fade feature to choose the start and end values. Since Vixen doesn't have much in the line of built-in RGB support, it can all be a bit tedious, but it works.