I thought it was the other way. If the led on the xenium is red, than the d0 is not correct, but the lpc is right. And if no lights come on than the lpc is done wrong.
When I first did my solder install I got the red led with fragging. I than redid the d0 and it has worked ever since. (After redoing the d0, the led came on but was green or yellow or somethin, dont remember)