lib/booktype/importer/docx/docximporter.pydoes support logging, so please try another import and then take a look at the end of this log file, with the less command:
less +G /var/www/booktype/instance1/logs/booktype.logProbably there is some discrepancy between the template of your .docx file and the format that Booktype expects. If you find any relevant output in the log file, please paste it into this forum thread.
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