The only thing you need to change are the .bik files.
Use RAD tools to convert various sound files into bik format. Then replace any sound file with your .bik file (must have the same name). You should replace all .bik files or alternatively you can edit the add.xml file and remove specific lines for specific files.
Make sure you rename the template name to your mod's name.
When uploading your mod make sure to tell people to install BeardLib and Hitsound Reborn and put the mod in mod_overrides not mods.