Aphrodite
Yeah, every object type is affected except for global types such as Function or Keyboard.
Near as I can tell, when a project is first opened by Construct, it stores an "archetype instance" of each Object Type in memory.
After some testing and from the way that the project file (*.caproj) XML is laid out, the archetype instance is simply the first instance (lowest UID value) on the first layer (bottom-most layer) on the first layout in order encountered that contains an instance of the object type (ordered from top to bottom in the Project Window Layout List) parsed by Construct.
Until a project is reloaded, the archetype instance assignment will not change. Even if you delete the archetype instance, Construct will continue to base new *EDITOR* instances on its properties/values. However, Construct on preview will reparse all layouts for the first archetype instances of all object types, which affects creation/spawn at run-time.
Also related to this:
https://www.scirra.com/forum/viewtopic.php?t=123150