I converted a few books from LIT to EPUB and noticed that Calibre is leaving behind what looks like some temp files, that don't seem to be attached to the spine of the book.
I noticed this due to how Sigil seems to handle these 'orphaned' files (inserting them into the spine arbitrarily). See the thread here regarding my initial rant:
https://www.mobileread.com/forums/showthread.php?t=87707
I'm not exactly sure if this is cause by a problem in the Calibre conversion pipeline, or my source .LIT files being malformed somehow. But even if the latter is true, I'm not sure it's necessary for Calibre to leave behind junk files like this, right?
The files it leaves behind are in a '~export~_files' folder within the epub itself.