I'm also trying to do the same thing. I was able to get code to decompress it, if you want a program, then Gramphos's Multitool comes with one that decompresses the sav file. The format still hasn't been fully deciphered, as far as I know, but they've made TONS of progress. I'm still asking around for it

I'll let you know when I get it if you want. you can email me at
kiran@joshi.com. Oh, if you get it before me, I would appreciate it