Hey, well done on getting to your first interview and good luck for it! For personal effectiveness, some of the examples I had thought up were times when I had to work to a tight time scale and how I prepared in advance and worked under the pressure to ensure that I was using my time effectively and what happened when things didn't go as planned. I think this is one of the questions they asked negatively for me - eg. when has your personal effectiveness let you down. So its worth thinking of times for each competency where your competency has let you down, but you've learnt from it.