Hello, I have been working on an addon for Blender to import and export .mu files. It is still very incomplete, but I have released it under the GNU General Public License (version 2), and it is available from github.
NOTE: The addon is now targeted for Blender 2.80. Those requiring 2.79 support should checkout the blender2.79 branch.
NOTE 2: Blender won't load the plugin if the directory name has periods in it, so if the resulting directory has periods in it, you will need to rename i