I was half-way through posting here about why I was still getting images showing “through” an image I had on the top layer when I thought the try putting it at “the bottom” and it worked! Just in case anyone else is fighting with this, it seems that the layers here run opposite to Photoshop. So the top layer is the furthest from your base layer image.
I didn’t have this issue before because I wasn’t layering a lot. But hopefully if you are having the same issue this will solve it!