Splasm Software Discussions

I got a problem while creating a very large audiobook with over 300 files.
The import option to iTunes is set and after successfully creating the audiobook the new book appears in iTunes but not with all files belonging to the audiobook (only around 70 files instead of 300).
I checked the content of the .abbuilder project files and it contains all files of the book.

How can this happen that the import to iTunes does not contain all files?
Is there any chance to re-import the project file (eg. by script) instead of building the book again?
(I tried to drag and drop the .abbuilder file to iTunes and I also tried to import the file to the iTunes library but without success).
Maybe you can provide an iTunes script to import a complete project again (iTunes script folder).

Thanks & kind regards
Frank