Klavaro uses the "gettext" package to accomplish internationalization. If you are interested in opening the possibility to enjoy it in your own language, you are supposed to work with a team in the Translation Project, translating the interface part (po-file).
To know more about po-files, see the gettext documentation.
In the "trunk" part of the Subversion repository there is a directory named "po", where you will find the file "klavaro.pot". Just copy this file to a new one, renaming it with the code of your language and using "po" as extension.
There are some programs to help on editing these files:
The advanced modules of Klavaro include some text to practise with. So we must provide a standard text file in your language, a file with the extension ".paragraphs". You don't need to translate it. Just create something new.
I could construct it, even if I know nothing about the language. For that, I could use articles from the Wikipedia. But, if I do it, certainly I'll include paragraphs about vegetarianism, Esperanto, philosophy, etc... :-)
We recommend 30 paragraphs, with an average of 60 words per paragraph. But that depends on your language. Some languages have mostly short words, others have many long ones... Here is the English example, only as a generic reference:
Klavaro's website is translated within the Transifex platform, allowing to do the work online, sentence by sentence. Anyone registered there may easily contribute in this area.