CS5.5 uses the old libraries, so yes, that swatch is missing. I'm not sure if you can download the Pantone+ libraries for free from Pantone if you've purchased the swatchbooks, but I believe you can get them if you buy the $49 Color Manager package: http://pantone.com/pages/products/product.aspx?pid=1017&ca=1
If you signup for an account you can download a trial which I think might install the ID Pantone+ libraries—the $49 gives you an application with extra management capabilities, which you might not need.
I was able to add the new 336 color guide to CS6 via the Color Manger trial.
If the installation doesn't automatically add the libraries you can add a book to ID by clicking the Fan Deck icon in the lower right corner of the manager, choose a book, then File>Export>InDesign.
After several attempts by myself and my colleges, we still cannot download a ‘FREE’ sample of the software.
It appears to us that it will only let you have the software FREE if you purchase something else!!!
If you can download the free trial software could you zip it and email it to me???
Did you create an account and login?
There is no requirement to purchase anything to receive a trial version of PANTONE Color Manager. The only 'requirement' is that you create a myPANTONE account which is entirely free of charge, and during the account-creation process you have the ability to 'opt out' of e-mail messaging from Pantone. For details, please send an inquiry via e-mail to firstname.lastname@example.org and we will address it directly.
Manager - Technical Support
I've put the solid and colorbridge process versions, coated and uncoated, into a .ase file you can download from https://www.yousendit.com/download/OGhjWGJIQVN6NE43czlVag