Suppose I have the following structure:
\RootFolder
\Folder1
\SubFolderA
\SubFolderB
\SubFolderC
\Folder2
\SubFolderA
\SubFolderB
\SubFolderF
\Folder3
\SubFolderA
\SubFolderB
\SubFolderQ

In the File Filter dialog, I need a way to specify "\RootFolder" in the "Folder" field, check the "Include sub folders" box, and include ONLY each of the "SubFolderB" folder contents. Essentially I want to exclude folders that are NOT "*\SubFolderB*" from the file filter. If each of the Folder1, Folder2, Folder3, etc folders above have 20 or 30 differently named SubFolders under them, putting them all in the "Exclude folder(s)" section is not feasible. You already have the "Include folder(s)" section in the Folder Filter dialog, it simply needs to be added the the File Filter dialog as well.