I am used to work with Photoshop. Unfortunately there is a bug in the paint bucket tool of Photoshop CS6. I made all updates up to 13.0.1 (x64).
Description: The paint bucket tool is very tricky to use now. If you want to fill a certain empty area of a picture with a simple color, it often does not do that. My clicks are totally correct, also the position ... but it does not take it. Somtimes I have to zoom insome 100% untill my clicks are successful and the desired areas are filled with color.
I hope that Adobe can release an update to fix that problem.