This is not a NEW license but renewal of your existing one. And no, you don't have to.
Active subscription is needed if you want to have access to upgrades, patches and support.
If you don't need that - your free to have expired license and you may continue to use JomSocial on as many sites you want.
- Instead of saying: 'it's not working', explain the problem in detail.
- Screenshots with the URL visible in them and the problem marked are more than welcome.
- Tell us how to replicate the problem, we can't fix it if we can't find it.
- Make sure that your site/server meets JomSocial System Requirements
- Make sure to setup JomSocial Cron Job
- Always provide us with access details to the backend and ftp. We need it to debug problems.
- If you have a similar problem, but a solution you found isn't working, open a new thread instead of 'merging' with an existing one.
- Use the "Thank You" feature on any post that helped you