rhaen
You could sort of "backup" /opt part of your firmware with the slightly modified Igorsk's flasher from PRS+ site. (button 5 would save it as new_opt3.img)
Localization is planned at some point in PRS+ project, but as you see, most votes went to other features: at the moment it's on the 4th place, after file manager, marking books as read and dictionary:
http://code.google.com/p/prs-plus/