WS2812B 64x8 Matrix issue

Impressed by the new 2D possibilities I decided to purchase a few WS2812B panels (these)

Testing with 1 panel first.

Doing some searches on the forum and my expectations where that these setting are OK but unfortunately I do not get more then the apprpx 30 leds blinking randomly.

Any suggestions? p.s. I have checked serpentine checkbox on & off



Solved. User error: Forgot to sync GND.

Leaving solution here in case others make the same mistake