Origin of Green vs. Purple

Color is related to the root pitch class of the horizontal scale. Like the circle of 5th widget

"On the one hand, I don't understand the what/why of what I see here."
There is a option to show more information in(on) the chord blocks and then maybe you can easier related this to the chord color?
 

For standard palettes the color symbolizes the key. With alternative palettes the root note is not necessarily the tonal center of the key

Eb major has purple as it seems, what for color has Cmajor then?

You should watch the video of pallette surfing with chord coloring, then you will see how it works and you won't need to delve into the technical details of how Cognitone coded it.

Here are the colors (dimmed)

consonance or dissonance of a chord wrt. the Key

No such thing exists. Consonance is primarily a property of the chord due to its interval structure, no matter which key you use it in.

What you seem to have in mind is how dominant-ish a chord is in a key. That's harmonic function.

The chords are colour-coded by type in the palette.

Then pay attention to the functional harmony of a chord progression. You can then choose chords with the same colour for variation in the progression, correct ?

How does this sound? You'll have to listen to find out.

The idea behind the colors in a progression is to see at a glance in which key (or horizontal relation) they are meant to have a function in. 

This way you can spot key changes, secondary dominants, etc quickly. Some jazz progressions show many colors (relation changes often) whereas classical harmony and pop often stick with a single color for longer stretches.

If color represented function, all progressions would look similar (colorful patches all along), and key changes would be obscured.

i don't see any coloring here , for this c major progression

Layout and coloring : default in  palette ? , what is it ?
André, I have the impression that you are the only one who understands :-)

I see the yellow color for C Major.

All palettes can use different colorings. That's not what you see in a progression. The progression does not depend on any palette coloring settings.

Yes, i noticed that too .
I think the palette use 4 main colors: yellow, blue, green and red for the distance of the tonica 
yellow : close to the tonica, functional related
blue: underway to and from the tonica 
green : neutral against tonica 
red: far from tonica 

But using Cmajor uses these colors, but A minor different coloring 
 

Default is yellow = major, blue = minor, green = suspended, augmented, red = dominant 7th

"Default is yellow = major, blue = minor, green = suspended, augmented, red = dominant 7th"
What to do with this knowledge ?

Yes both summaries are correct

I took another look at the video of the palette, but in order to learn the finer points of building a chord progression, this is of course a joke from a didactic point of view.

Click on that chord and then on that chord, even a monkey can do that :-)

Well, how to treat a chord progression musically is a different story, rather than a technical one.

Well, how to treat a chord progression musically is a different story, rather than a technical one.

Exactly. The video is a technical instruction only. The other video about coloring schemes is more practical

Could you please state more clearly that this video deals with technical aspects and has no musical significance for the chord progression shown?

I have often noticed that André's products lack user-friendliness in essential areas.

In the palette 

Layout : default  ?
Coloring : default  ?
Is this information useful for a user, yes or no ?