4
Did you download the core spanish files? Go to the
xoops core language files and grab the spanish language pack. Notice that the core /language and your modules /modules/xxx/language directories should have at least english & spanish sub directories.
Once that is done then all core data like navigation etc is changed to the selected language. This isn't a translation system though, you have to do the initial content translation and surround it with the tags as per the Readme.
buena suerte,
saludos de Canadá