Latest Kdenlive 0.9.10 installed on Ubuntu 15.04. Once Blur and Hide > Auto Mask effect is created the bounding box cannot be selected and Analysis does not appear to work.
You can edit the bounding box if you put the cursor on the start of the clip where the effect is added. But if the cursor is elsewhere the bounding box is not editable. Analysis will work if you start at the start of the clip. This is an anoying limitation because it means you can not start analysis in the middle of a clip. Simple workaround is just to cut the clip where you need the Automask to start.
Seems the function was working; but another misalignment bug has just been fixed for 15.08.1.