It is a content issue; the phantom objects appeared during NeoLemmix-ization of these levels (hence why they wouldn't be there in the DOS version opened in the traditional Lemmix editor - not that the DOS versions would reveal the problem anyway, as NeoLemmix's content used the Amiga version as its starting point). Either that, or it's a bug in the dumping code. No, the dumping code hasn't been changed in ages, and I just checked now with the new NXPs that have the content fixed - they no longer have this problem. It's definitely, beyond any doubt, a content error, that has now been fixed. As such, closing this topic now.