To automate adding of maple-www.js script to worksheets that your users upload to the server, you can create scripts/cron jobs/services that listen the folders and automatically add the script to the new/updated worksheets.
The script should be added after the point where the <Worksheet>
In this case, your users can smoothly upload and update theirs worksheets and always have them openable in the web.
Maple WWW includes ready-to-use tools and scripts for most common servers.
The tools are available for users with Premium Support