If it is easier for you to follow your Google+ friends activities using RSS Feeds, then the web app called Google Plus User Feed is just what you need; and the configuration is really simple.
What you need first is the Google+ profile ID of the user you want to add to the RSS Feed. To get the ID, visit the user’s profile and from the URL grab the long number.
This is how the Google+ profile URL looks like https://plus.google.com/102573812580450550810. This number 102573812580450550810 is the ID.
Now insert the long number to this Google Plus User Feed URL http://plusfeed.appspot.com/. After you do this the URL will look like this: http://plusfeed.appspot.com/102573812580450550810. And this is pretty much all you have to do, next is to add the newly create URL to an RSS Feed reader of your choice, like Google Reader or another feed reader to follow your friends’ public updates via RSS Feeds.