Tested working on windows 10 (x64)
- Download the .bat file "convert mkv to mp4.bat"
- Make sure FFMPEG is installed to C:/ffmpeg (if you installed it at a different location, you can edit the .bat file)
- Place the .bat file in a folder
- Copy some .mkv files into the same folder
- Double-click the .bat file and it will begin converting the .mkv files to .mp4 files
It should preserve all of the audio tracks and process fairly quickly. It isn't re-encoding, but just extracting and placing in a new container.
Submit any issues to the issue tracker and hopefully I can help