Getting Started
When you launch the program you need to click the "list files" button to get a listing of files. This produces your current working set of open files. If you type something into the filter, sort the columns or change a volume view it will work this this file set.
How do I reload the file list?
Just click on the "list files" button and the list will reload.
Why can't the list auto-refresh?
The list of open files is obtained via the unix utility lsof. This utility is very CPU intensive and refreshing the list over and over would eat significant resources. If you want to watch realtime system resource usage you should use Apple's Activity Monitor.