This mod replaces the standard vehicle editor music with the Harvester Editor Music (A cancelled editor). To install it, just use "Spore ModApi", or drop the .package file on the data folder in your Spore installation.
Just enter to any vehicle editor.
The music was already inside the game, I just enabled it. It was under the name music_harvester_editor.pd / .pdr
The harvester editor is the editor for a vehicle known as "Harvester", it was going to be used on the now cancelled "City Stage" of Spore. It appears it was repurposed for the Civilisation Stage but ended up being cancelled anyway.