After getting nowhere with this thread: http://forums.buffalotech.com/buffalo/board/message?board.id=0101&thread.id=4478 I contacted buffalo support. They sent me the instructions to do a firmware update (which I thought I'd done but apparently not).
The firmware's now updated and I can see my LS Live again. Yay! Except, wait for it, only one of my 2 shares is visible.
I had 2 shares: "Share" with 4GB of data, and "Media" with about 200GB. The files in Media are still there because my 500GB drive is showing as nearly half full, but I can only access the "Share" share. Is there any way to get at the data in Media? Even if I can copy it off the NAS I can format the disk and copy it back, I just don't want 200GB of data taking up half my NAS when I can't access it.
Oh I tried simply recreating a share called media, but it's empty :(
Any ideas?