Bad news! PDFs can not be imported into iBooks Author. Only Chapters created using MS Word or Apple Pages. I am not familiar with CreateSpace or their requirements.
iBooksAuthor requires the text and images to be set within one of the free templates or your own customised template. Your Graphis guy should be able to supply you with a conversion from PDF - but its more likely he will have created the book on MS Word already, in which case you ask for that and adivise you need text and images.
IF he/she can supply the original in MS Word, you can import it into iBooksAuthor - but I doubt it will convert as you think it should.
While for me and others, stripping out a PDF and re-assembling into iBA although tedioous - is at least an option.
iBA is really quite easy to use IF you take the time and trouble to read up and practice before setting out on your masterpiece.
Start be reading the help files and have iBA open with the Basic Template and just move or change things!
I and others here will more than happy to help you as you need it.
Its not as daunting as it sounds... its like Powerpoint or similat where text and images can be added to a page.