So I decided to make a personal "home" out of a dungeon using custom tileset assets. I didn't want to build a brand new cave so I made a duplicate of Broken Oar Grotto. I went through and painstakingly removed all the wood/spawns/etc, and then started adding my own stuff. While in the editor, I did notice a lighting anomaly at one point. There is a very large structure that spans from one cell to another, and a light in one cell wouldn't affect the object because the center of the object was in another cell.
This didn't bother me, I worked around it. However when I got in game I realized that it was an indication of a larger problem. Apparently, it's only loading my current cell while I'm inside. I can literally be standing in this large room, and the back wall is missing because it is in another cell (at least, I believe that is what the issue is).
I step into that cell, the objects become visible, but many or most of the objects in the cell I left become invisible.
What's going on here? I am not experienced enough with the CK to understand what is happening. I know this does not happen in the vanilla non-duplicate version of this dungeon. It is affecting vanilla objects and not just the custom assets.
Thanks for any replies.