The error says "Cannot find view element with ID", it means in the View, the view element its not able to find it. I am not sure if you are adding this or something which is missing from SAP.
Before your chnages, was it working.
If yes, let us know how are you making the chnages?
1. Try personalization though the content admin
2. From the Self Service Admin i.e from FPM config, see if you can chnage the titles