Also notice "The character 'NEWLINE' is not allowed in 'STRING' expressions" which indicates that maybe a closing quote or double-quote is missing somewhere. The -1 can also mean that it's right at the beginning of the file and the scanner (wrongly) hasn't started counting lines/chars yet, or you have so many lines/chars that the scanner overflowed while counting :-)
Can you tell us more about the .epub archive? Where it came from, how big it is etc? It may help to remove files to narrow down which one causes these warnings.