I've been noticing this for a while. Even though the cookies are listed under Cookies to Delete when run the cleaner does not pick them up. Cookies that are not cleaned for me are:
cdn.tremormedia.com
flash.quantserver.com
static-cdn1.ustream.tv
Version of ccCleaner 3.18.1707
Browser Firefox 12
OS XPPro
Your CCleaner version is out-of-date, perhaps try with the newest version 3.19.1721
go to the applications tab and place a check mark in adobe flash
Ah, just found out why those three aren't being cleaned. They are Flash settings cookies and are being protected by the Firefox Better Privacy addon and are in a protected folder. As I didn't need them I deleted then via Better Privacy addon. Mystery solved
Glad you got that worked out