I came here looking for some info myself for I have the same problem. I cant count how many times I have glitched, tag'd, flashed, drilled, etc., so I am very familiar with, am no where near a noob, and do have common sense! lol But anyways, I just finished a zephyr all the way to the end, and at testing the first boot before removing nandX wires, it will not respond at all. Psu light stays orange, no solder dropped anywhere, very neat job! I removed everything and still same thing. I didn't include pics because I am not necessarily asking for help but more commenting on this thread, not jackin! And I agree with one of martins old post in that I have never had even a small issue with zephyrs, just this weird situation....
I happen to be nice (an idiot) and loaned out my mm and will check my points in the next few days to see if there is an answer there, but dont imagine something crossed and need to reball. It was never really on but to retrieve my key, but possibly enough though.....