Norton Identity Safe and N360 Premier Update 6.2.1.5 with Google Chrome

I have been using Norton Identity Safe / Norton Toolbar with Google Chrome for some time now, and have been reasonably happy with the way it has been working. However, since receiving the latest Norton 360 update (6.2.1.5), the following issue has (unhappily) appeared:

I have my Norton Identity Safe configured so that it automatically logs out after 15 minutes. With that working correctly, I can be confident I will be protected if someone breaks into my house and steals the computer while it is running (Don't laugh it has happened to me before). However, since update 6.2.1.5 was installed this feature only very occasionally works. By this I mean that the automatic logout after 15 minutes fails to occur. 

Can someone please help me overcome this problem, or tell me how to get rid of the update.

Many Thanks

Michael