Attached is the latest version of my FindIt! program which uses this "new" control to exclude files from a search. (I've been using it with search terms like .jpg, .exe, etc. Program doesn't need wildcards, like *, just text.)
The exclude listbox works fine, compliments, but its functionality seems not implemented
Re "doesn't need wildcards", most users would search for *.txt or similar and be very surprised not to find any files

For comparison, I attach my version. Some differences:
- wildcard search, e.g.
*.as?|*.inc|*.rc (finds/searches text in *.asm, *.asc, *.inc and *.rc files)
- if the "text" edit is empty, find all files, otherwise only those that contain "text"
- hitting Return or clicking Go! starts the search
- window is fully sizeable