Use the Contact Us link at the bottom of the page. You can leave a call-back number, and they'll likely get back to your in a timely manner. CreateSpace uses various printers and minor differences are to be expected, If the problem is major, as yours seems to be, they'll probably ask you to send them a photo to prove it and then they'll replace the book forthwith.

As you have discovered, CS has a good warranty and they do stand behind their work.  Just in case:

https://www.createspace.com/Special/Help/Rights/Guarantee.jsp

At the risk of sounding too simplistic, every press that CS uses and all the press CS's subcontractors use are capable of printing perfect color.  Once CS has adjust our PDFs . . . and this is important: CS does remove some all color information from our files . . .

Color.Profile/ICC.Profile – Color management added to an image or file, which KDP will automatically remove prior to publication.  <pg 5 KDP Print Publishing Guidelines>

Color.Profiles

We do not recommend including color profiles in your file. Color profiles are automatically removed prior to publishing, which can produce unexpected results.  <pg 16 KDP Print Publishing Guidelines>

A printer recieving work from hundreds of different sources a week, if not a day, sources that might know nothing about color space and color management, would usually strip away all color information and apply their own profiles, Indigo, phone conversation

however, once that's done, each file should print correctly on all presses.  The problem is that all presses drift out of calibration. If calibration and maintenance is done well, things should be ok . . . but it takes time and time is books/money/sales.  All that said, even conventional printers doing long runs (not print on demand), can print crap.  It is what happens.  Presses are big and dangerous machines, and I sometimes things it's a miracle printing works at all.

  Walton

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