Is it me, or is the "make invisible in editor" option gone from 103? Without it you cant see, or directly edit, objects under other objects - you can highlight them with the "object list" thing on the right, but when you right click on a single instance to edit animations etc in the layout window, you get the top most object. Obvoisly we can move the top objects out of the way, or send objects to the back, but to make groups invisible was handy.
We avoid the use of layers as far as possible, as when you add or remove a layer, you have to go through all the event sheets editing by hand anything which referenced a layer number as they all change. A great enhancement for a future version would be for the actions to access layers by name or internal ID, not by the order number which changes all the time.