Userscript for downloading high-quality scores and audio off Musescore for free. Download TamperMonkey here, open the script, and copy paste its contents into the 'new script' tab in the TamperMonkey UI.
If you already have Musescore open in a tab, refresh it and the TamperMonkey extension should light up with a red '1' symbol. Look at the bottom right hand corner of your screen and the download buttons should be there.
It is important to note that THIS IS NOT MY CODE, and am uploading this solely for personal modification. The script links here for updates, and this is where the source is found. Kudos to all the contributors at LibreScore for their work on this script.