Hi Elco,
I changed this line some time ago, seemed legit when I did that. I've changed it back.
I edited the code so the number of Shift Registers is now 5. What happens? Nothing :). It's now testing every color at it works. Only the 11th "imaginary"-Stripe is tested so all the lights are off.
Currently I'm just using one capacitors with the first register.
Is 1 meter already a "huge" distance for the Arduino?