MKVPropEdit GUI is a wrapper for mkvpropedit console application by Moritz Bunkus. It provides quick, easy and friendly way to edit MKV metadata such as: overall title, track name, track language, track flags, ordering of tracks.
Software is distributed in binary mode together with two necessary console utilities. All binaries are UPX-compressed (if your anvivirus software dislikes these binaries, just un-UPX them). Source code is not distributed because despite it's quite trivial it uses some libs which are not ready to be released to public yet.
Run the software, paste path to a MKV file and press [Load] or drop it from Explorer onto the application window. Do some changes then press [Save].