The default HSMX installation we provide comes with English as language. It's possible to translate the entire web-interface, captive portal messages and help-files into your language. HSMX comes with built-in tools to create new translations. Browse to System → Language and enable Language update.

This will add -icon to the right sub-menu bar. When you browse to another web-admin page you'll be able to translate the labels, messages and help-file of the page.