I got around to setting up my new P2 last night. This was my first time using pixel controllers! The P2 was really easy to set up and the videos on this site were excellent. So why didnt it work? Why didn't my pixels light up? I gave up trying to answer these questions around midnight. After spending another hour tonight problem solving I learnt a few things... 1) If its your first time setting up pixels, dont try it late at night ,when tired, after a long day at work. 2) Wiring diagrams from China might not be correct. 3) Dont assume that the black power injector wire is connected to the black wire in the pixel string. 4) The ground wire doesnt work very well when used as the clock signal in a WS2801 pixel string. 5) It is so easy to configure the P2, reconfigure it, upload new firmware, and reconfigure again via the USB port and utility. 5a) It is also easy to repeat the whole configuration exercise again using the web viewer. Finally I found the problem - swap the ground and clock line at the controller and the pixels worked perfectly! Thankfully no damage was done to anything other than my pride. :-[ Hands up if you would have guessed that the black ground wire (in the power injector pigtail) would be connected to the yellow 'clock' wire making what normally would be the clock wire in fact a ground! Thankfully they didnt swap power and data! My advice: double check the wires before you connect power. Then when you are about to plug it in, stop, and recheck the wires again. I dont know how the P2 would react to using +5v (or +12v) as the clock signal!