Sorry for leaving the thread on a slightly sour note. You hit a sore spot. I'd finally gotten 24 AWG wires that day and was proud of finally not having a rats nest of mm dupont wires. But I'm sure you're right, something's not right with my wiring. I've got the new maxes and it doesn't help to swap it out.
Here's an album with two attempts, one with a multicolor led on dgt 0, seg A-C, and one with a single 7seg on digit 0. Both just stay on even if I toggle shutdown, or toggle 0x0 and 0xFF on digit 0. (Edit: I see I wired the multicolor led inverse, ignore that. The 7seg is correct)
Hope these images are better.
Including one here for easy access.
NB! I ripped out the V+ and GND from the breadboard to make it easier to see. That's not the reason it doesn't work. 
