I've tried several times to import book chapters in a few formats (importing the zipped folder resulting from saving docs as HTML... I've done it from PPT and PDF). I get the same errors:
Warning: Invalid argument supplied for foreach() in /home/9/7/5/23608/23608/public_html/moodle/mod/book/lib.php on line 315
Warning: Invalid argument supplied for foreach() in /home/9/7/5/23608/23608/public_html/moodle/mod/book/lib.php on line 318
Any thoughts? Thanks!