Along the many issues with BodySlide, I noticed that it sometimes didn't create all the meshes for me when I was running it directly on my Skyrim installation. Of course, without showing any indication that something was wrong. It ran through without errors and reported a successful execution. But that was a lie, it didn't really do its job.   Try setting a different output directory in BodySlide (e.g. C:\BSTemp) and then manually copy the files created there into your Skyrim\Data folder, over