Hello everyone I am also suffering from this bug. I am on ps3 and I have to say this bug is ruining my entry. From what I gathered every time I save it duplicates something. Not really sure what causes it tho.
Read my entries here in this thread and watch the video in entry #16, you'll see that I found out why it did in my level.
Did you find a way around the problem? I watched the video and was going to ask if you tried using a Destroyer to get rid of the bugged objects.