The easiest way to extract the cell with the maximum (or minimum) value is to use Find Data 
(about the middle of the top toolbar or in the Edit menu). Create a selection criterea of Cell element types and where the field is max (or is min).
After you click Find Data button, the element will be highlighted in the 3D view and will be listed in the find data dialog. After that, you can add the Extract Selection filter 
. Your selection of the maximum (minimum) element will be copied to its parameters, and when you Apply it, your element will be extracted.
