So I now currently have 2 blinking reddish/orange LEDs near the arrow keys on the bottom row and one solid bright pink near Esc. I'm pretty sure all of my LEDs are on correctly. They all briefly flash when I unplug and then plug it back in.
That seems to mean the power pins are connected OK but the data pins are not. The pin with the line next to it is GND, and the pin kitty corner from that is VCC. You don't have to mess with those if it flashes when you plug it in.
The first LED is the one by the arrows. The pin closest to the bottom row, on the same side as the pin with the line, is the DIN pin. The pin kitty corner from that is DOUT. You can trace the chain around the PCB from there, finding the second LED between SLASH and RSHIFT. Follow those around one by one, double checking the solder joints at the DIN of the first one that does not light, and DOUT of the last one that lights.
I'm sorry I haven't had a chance to get the firmware built and double-checked yet. I'm working on it still.