Today; I verified the Nixie Pinball Display as completely functional.
I populated all the nixies on a FabB Display board; installed all the backlit LEDs and ran the full test against it.
All the digits work; and the emulation works as expected. Setting A5 = A6 = 1 emulates the 7th digit.
I haven’t checked for the 7th digit in non-emulation mode; but expect it to be low hanging fruit.

I did find that the 300k resistors along with the 110V “bias” voltage via Zener was necessary. Without the bias; some digits would see ghosting in non-active digits. By driving the anodes and Kathodes to 110V when not in use; the digits won’t flicker.

Here’s a video of all the digits working:
http://youtu.be/7Eys2KxI20g

Next step is to finalize FabB of the base and display boards while the changes are still fresh in my mind.