Rebuild your Song Database then retry entering a batch of MP3+G files. Be sure to create a page (or pages) for your songbook of the files that did load
BEFORE you rebuild the Song Database so you'll have them to put in your books as "New Songs".
I ran across the issue of Hoster going to "1" for the "BookID Root" automaticaly one time after a power outage occured at a gig. Rebuilding the Song Database solved this problem.
I Hope This Helps
Jim