Thanks for your inquiry. I have managed to reproduce the same issue at my side. I have logged this issue as WORDSNET-7537 in our issue tracking system. I have linked this forum thread to the same issue and you will be notified via this forum thread once this issue is resolved.
We have a good news for you that is WORDSNET-7537 has now been resolved and its fix will be included in the next version of Aspose.Words (v13.1.0) which is planned to be released by the end of this month (around January’ 31, 2013). We will inform you via this forum thread as soon as the new release is published at the end of the month.