in order to make a copy for color proofing I have download and installed (Windows 7/64 in WINDOWS\system32\spool\drivers\color.) ICC Blurb but my LR 5.7 does not recognize it. No problem with all others ICC.
LR 6 and CC 2015 support CMYK profiles in Soft Proof, but not earlier versions:
Soft proofing and ICC Profiles in Lightroom : Blurb Support
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