This happens in 6.7 Beta 1 repeatably for some but not all documents - I have seen it in the 6.6 stable version as well and it has been reported in a recent thread (presumably 6.6 latest stable with a different OS/Office combination): https://community.logos.com/forums/t/117180.aspx
While the books compile well, the PB compiler log of the book contains error messages as such:
[Error] Document contains an unsupported VML image which will not appear in the final document. To use this embedded image, open the document in Word, select "Save As...", and deselect the "Maintain compatibility with previous versions of Word" option. Then rebuild the book.
Running Logos 6.7 Beta 1 on Win 7 (32 bit!), I'm compiling a Word document that I prepared under Word 2007 - there is no image in the file, let alone a VML image (a Microsoft page tells that this was a vector graphics format deprecated with IE9), and I don't see such a compatibility option in Word 2007 either.
3678.Adolf Schlatter - theological method.docx
PB-log
7384.PBB_a11bc3e16cae4eaeb5daa7a8712a8f44_2015-10-04T20_26_53Z.log
(The same error occurred on my 6.6 stable version on Sept 27 when I compiled two documents, SS Lesson 2015 3rd Quarter Teacher and Standard versions, found here: https://faithlife.com/adult-bible-study-guide/documents )
