I went looking through all of the nibbler recordings today - and lo and behold, it's not the hardware that's causing all of the trouble, it's MAME! that's causing all of the trouble, although they wouldn't admit it :)(posted 9606 days ago)How do I know this? When I saw Phil play his excellent 9M game, on MAME 34 FINAL, you will recall that he had levels expiring before he was supposed to finish the level.
When I saw another recording, this time on MAME (35) FINAL, I never saw this error. Perhaps this is why Phil's game expired at Level 92(or around there) instead of continued.