Un-zip this patch to the /Interface/AddOns folder, just like any other AddOn.
Make sure that you ALLOW IT TO REPLACE any existing files.
This is an Optional Patch for MapNotes (Fan's Update), that replaces the new style default icons, with the original ones that came packaged with the AddOn years ago
No .toc or .lua file is included in the zip file - just the original graphics icons which will overwrite the new defaults.
Use this patch if you can't be bothered using the MapNotes_IconLibrary to change the defaults yourself.
NOTE: this patch will need to be re-applied after every new version of MapNotes is installed.