I’ve used it before in previous versions but I can’t find it in the Levels dropdown after enabling WC in 4.12. I saw that one of the features was the ability to import .png files as tiled landscapes, so I’m hoping it wasn’t removed?
Did you ever figure this out? Trying to find it myself.
That’s what I was looking for. Thanks. 
Click the icon in the top left of the Levels tab.