Hi! Thanks for the guide. If you have time for a couple of questions.
1. Why is there an extra 10 LEDs between some of the LED strips?
Sideboard Left starts at 257, and has 134 LEDs. The next LED in line would be 257+134+1 = 392, but the guide shows 401.
Sideboard Right starts at 401 and has 134 LEDs. The next LED in line would be 401+134+1 = 536, but the guide shows 545.
2. Does this work with OTHER Arduino boards besides Tiny? I have a lot of Mega 2560s laying around.