Just made the move from CS6 to CC15 and first impressions of InDesign are really disappointing. When I edit some text there's really bad lag as it renders changes and often the text you have highlighted will 'disappear', in that it goes invisible until you click on something outside of the text box.
I'm on a fairly current 2.7 GHZ iMac with 8GB of RAM which was more than sufficient for running CS6. Display Performance is set to the default 'Typical Display' setting.
I just had a similar problem. It was the open CC Library (I'm traveling with a really slow internet connection).