I'm having some hard time (but still fun) finalizing the translations and multilingual support for Slax. Lately I was making FireFox talk in your native language :)
My first impression was terrible, I found firefox offered only as a whole package bundled with international support. That wasn't usable, so I searched more and found distinct packages containing just translations. It was not obvious how to actually make the extension work at all, but finally I found some article which helped with that.
Yet there was another problem, how to make the extension auto-install in FireFox - the browser has some strange feature that it informs the user if extensions were installed using an external program, asking if the user wants the extension or not. I found that rather disturbing. So finally I've made an bogus (empty) extension which I install to firefox, and then the language xpi overides it. Not a perfect solution but it works.
I've also applied some nicer theme to firefox in Slax, since it looked just terrible. One developer is working for me on an addon to get rid of the title bar, to save some more space on screen.