Questions about hidden units/buildings in the scenario editor

I’ve been tinkering around with the Genie editor and I have two questions about hidden units/buildings in the scenario editor:
1)How do I make them appear in the scenario editor selection menu? (for example ABGAL which is the boarding ship that is used in Filthydelphia’s Francis Drake custom scenario, tho I can’t find it in the scenario editor after unchecking hide from editor)

  1. I’ve enabled fortified gates and I was wondering if it’s possible to make them rotatable like the stone/palisade/sea wall gates

Thanks.