The "Status Bar" is a small space used to display information regarding the select file, the total number of files in the folder, etc. It can be found at the very button of the CKFinder interface.
If a file is selected in CKFinder, the Status Bar will display detailed information about that file, containing the file name, its size and the data of its last modification. For example:
If no files are selected instead, the total number of files in the current folder is displayed. For example: