I was having this same problem with Chrome ver. 13.0.782.220 m on Windows XP.
My fix was as follows:
If you go to Chrome >> Spanner icon >> Options >> Under the Hood
The very last option is "Background Apps" with a checkbox "Continue running background apps when Google Chrome is closed"
When I unchecked that box, CCleaner finally ran without the message about closing Google Chrome (when it was already closed).
I don't think I have ever signed up to Google Cloud Print or Synch so that wasn't a factor for me.
This Google thing only happened to me and CC since I grabbed the latest version of CCleaner 3.10.1525 about 10? days ago.
Thanks CCleaner I love your work!