Thanks for the reply. I think I have the right version of the pro micro. I’m using this from Amazon: https://www.amazon.com/gp/product/B08THVMQ46
I double checked the orientation of the led strips. Data in is going to the arduino.
I get lights at start up, but they look weak. Then the right-most LED stays on bright white and won’t turn off.
I’m wondering if the wire I used was too small. I used some strands from some old speaker wire that I had, but they only measure about 0.1 mm rather than the 0.3 mm that you suggest. I may need to start from scratch and find some larger wire.