As a followup to the LCD issue. I don't think it's the LCD.
I was able to reproduce the problem, and with tracing on, here is what I got:
Code:
instant: 0,0,0,0
current: 0,0,0,0
instant: 0,0,0,0
current: 0,0,0,0
instant: 0,0,0,0
current: 0,0ü
Notice the funky character - the Guino apparantly crashed. I've repeated the experiment multiple times with the same basic result - inoperative unit.
I'll continue to investigate.