Here's another TWIST to the problem.
Stupid me, for not thinking about it before asking.
It is the LED node that is the problem.
Proof:
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Well, could someone check this and prove me right or wrong?
Scenario:
Two machines needed.
Both looking at one of the machine's Dashboard.
From the dashboard, press the START button.
The BULLSEYE will blink on that machine and the remote machine.
The LED will only blink on that machine.
Go to the EDIT screen and try there: LED will blink on both.