Hi Rolf- I have a Mayfair that does the two alternating relays (A and A1) and is otherwise the same except for no other relays in the circuit. The two handle the red and yellow bonus ladders, which alternate. https://www.ipdb.org/showpic.pl?id=1562&picno=6543&zoom=1 U (Double Target Value relay) handles that on its own.

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Hmm. The A1 switch on the orange path feels like a lock in switch to me. The U, V and X relays all have their own lock in switches that once activated keep them active for the duration of the Score Motor cycle until the Motor 2B switch opens to release them. So those three switches would keep the A1 relay from relaxing while the U, V and X relays are active.

I wonder if the orange path is intended to keep the A1 relay active through the end of the Score Motor cycle only if the motor is running because of the U, V or X relays. Perhaps if the A1 relay were to relax while a Roto Target is spinning for example the scoring results would be unpredictable or annoying if it changed from 50 to 5. Although apparently the A1 relay can activate any time 10 points are scored, even while the Roto Target is spinning, so there's probably more going on here.

/Mark