This window opens on clicking the "Manage media" button on the main window after you select a virtual folder of the project.
The left side of the dialog practically copies the rules manager panel of the main window. You can add, remove (or cancel deletion) of the rules, move them up and down. Also all changes since you have opened the dialog may be cancelled by clicking the appropriate button.
The listview on the right shows files information after you click the "Run test" button.
Choose the computer or any of the connected storage devices in the combo box and run the test. All files subject to synchronization according to the rules will be marked green. Others - red.
The list may be sorted up or down by clicking the column captions. You can also set a filter which will help you to to get rid of irrelevant files. The popup menu, called by right-clicking the list, contains all available filters. Besides, it introduces commands to add rules in context of the selected file.
After modifying the rules set run the test again. If you're sure everything correct click "OK" to save the changes. Otherwise click "Cancel" to close the dialog.