Licenses work on multisites or even multiple isntalls as long as they are on the same domain. For example http://www.yourdomain.com/region1 to http://www.yourdomain.com/region7 will work, however region1.yourdomain.com will not work and will require separate licenses for each if you are doing separate installs.
You would need to do a WordPress multisite install and validate on the main domain meaning set the API key for that domain. In a multisite install you can set it to use folders (www.yourdomain.com/region1) or subdomains (region1.yourdomain.com) the main domain controls the theme settings accross all sites so if you validate there it gets passed down to all sites within the multisite network.