Fixture 78 (Narcissus launch console). Intended rule: the launch is COUNTERMANDED (msg #28) unless every living crew member's room is 34 (Narcissus); then Jones must be aboard too (JonesRoom = 34, or the cat caught and the Cat in Net/Box item aboard or held) or msg #27 "BioUnit Jones not present" fires first.

BUG (simulator-verified): the crew walk drifts off the +7 status column after the first LIVE crew member — the "back to the next record" step adds 8 from the +1 room byte instead of returning to +7, so every later slot has its ROOM byte read as a status byte.

Rooms are almost never 0, so later crew are simply skipped: the launch really only requires the first-listed living crew member (plus Jones) to be aboard, and the rest are left behind. The one side effect: a later crew member standing in Airlock #1 (room 0) bogusly countermands the launch.