I would switch to using ndbm, as it is a bit more self-contained:
http://neurosdbm.sourceforge.net/The latest official firmware is here:
http://www.neurostechnology.com/taxonomy/term/8And if the 20G backpack works fine, you may want to call Neuros directly to see if they still have parts to repair the backpack. As far as I know, it is just a battery and a converter board (the memory is in the brain, used as cache for the HDD backpack), so there may be repairs you can make yourself... I've not had a battery-only backpack open yet.