I think you need to Trim the Zone body to the Roof the Skylight is placed into.
Then the From Zone /Zone Number and To Zone/Zone Number fields will return the correct values for the Skylights in the Schedule.
At least it works for me in AC21 build 5010.
Interestingly, according to my test, if you use the Crop Zone command instead of the Trim Elements to Roof/Shell command on the Zone, the fields will not return valid values. So you need to use the Trim Elements to Roof/Shell command.
I am supposing that the reason the Crop Zone command does not return a valid result is because this command does not create an associative connection between the Zone and the Roof it is cropped by.
And that the reason the Trim Elements to Roof/Shell command DOES return a valid result is because this command DOES create an associative connection between the Zone and the Roof it is trimmed by.
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