Either way, may I ask why it was deemed necessary to break a deadlock. Surely a draw is a perfectly fine result, or does every match need a winner due to a detail I have missed? Again, not being critical of your format, just making sure that I fully understand it.
I was curious about this as well. Draws happen in competitions and as long as it's not the playoffs/championship they don't worry too much if it is a tie as they have eventual tiebreakers when it comes to moving out of the pool.
Forgot to get back to both of you on this, sorry!
The relevant information *is* explained within the quoted text in my opening post, but I'll see if I can explain it a bit better now

basically, at the end of the first stage the top three contenders in each league progress to the next round; placement is determined initially by "
total matches won", and if there is no tie-break required the matter ends there. So for instance, with numbers and collections invented off the top of my head.....
Sofia -
4/5 won
Lisbon -
3/5 won
Bratislava -
3/5 won
Marwell -
2/5 won
Riga -
2/5 won
Rome -
1/5 won
.... the three collections progressing would be Sofia, Lisbon and Bratislava. However, if the scores went as follows....
Sofia -
4/5 won
Lisbon -
3/5 won
Bratislava -
3/5 won
Marwell -
3/5 won
Riga -
1/5 won
Rome -
1/5 won
...then we'd need a tie-breaker between Bratislava and Marwell, in which case "
overall average score across all matches played" comes into play - and if Marwell had a higher average than Bratislava, the former would progress whilst the latter would not.
As this scoring/progression format (devised, as previously noted, by
@CGSwans ) doesn't allow for half-points for a tie, the Plzen/Pairi match needed a definitive winner - but equally, retaining the genuine "
points-percentage earned" minimises the impact this will have on the potential progression of either collection.
I can't really participate much other than Group C, as I've been to four (technically five) of the six (seven) competitors there. Nonetheless, I'll be happy to share my thoughts as and when I can.
Again, there is no reason to abstain from participation

a large part of the motivation for the Cup is to provoke discussion and debate, and to help people learn more about a wide variety of zoological collections! Even if you don't ultimately vote, your questions and feedback may help others to make their own minds up, and encourage people to share their own knowledge and experiences.