Custom Build Ability?

[Nesferatu]

Hello, I'm very new to the Galaxy editor.
I am trying to find a way to make a custom build ability, one that would not require you to open a build menu to choose from several buildings.
Instead, I want the building to be built on the unit's button list right away.
For now, I managed to add abilities etc, but the building "cannot be placed" anywhere, nor does it have any models (green orb), although I can totally place the unit specified in the build ability. I think I did something wrong while assigning the building to the ability, can you guys help?

 

[Dr Super Good]

Make sure the actors are correctly set up. Also make sure the buttons are linked to the correct abilities.