(The 32-vs-255 was to check to see if it’s a power issue… seems not, or at least not a big one.)
Looks like something’s not right with loading the hex values from the list of colors you put in.
You said that it’s flickering? Could you describe in more detail, or maybe take a short video?
Find this line:
CRGB color = myColors[ index ];
and replace it with this:
CRGB color = pgm_read_dword_near( myColors + index );
When using data stored in PROGMEM, you have to use “pgm_read_{type}_near( {address} )”. My oversight.
Regarding power i’m using a 10A powersupply, the problem can’t be the power, i’ll check the last solution you suggested
it works !!! I have to celebrate 
I noticed some color difference from hex values and the displayed colors, calibration is required, the green part on the left is showen as cyan … not really cyan but almost
There also some flickering, how describe it … it’s like caustic light under water I tried to capture it using my old smarphone but the photo sensor is too scratched, I’ll buy a new one
I celebrated 40 minutes ago
here is the art I user, a wenderfull piece of Leonid Afremov https://afremov.com/image.php?type=P&id=18582
@Mark_Kriegsman thx again, without your help I am certain that I’ll not get what I wanted
Happy to help with the project!